Screen assembly for vibratory separators

ABSTRACT

Screen assemblies for a vibratory separator and methods of using them, the screen assemblies in one aspect including a first screen portion having a first end and a second end spaced apart from the first end, a second screen portion adjacent the second end of the first screen portion, the second screen portion projecting down from the second end of the first screen portion.

RELATED APPLICATIONS

This is a division of U.S. application Ser. No. 09/820,179 filed Mar.28, 2001, now U.S. Pat. No. 6,607,080, a continuation-in-part of U.S.application Ser. No. 09/707,277 filed Nov. 06, 2000, now U.S. Pat. No.6,581,781, which is a continuation-in-part of U.S. application Ser. No.09/696,662 filed Oct. 25, 2000, now U.S. Pat. No. 6,629,610, acontinuation-in-part of U.S. application Ser. No. 09/634,610 filed Aug.05, 2000, now U.S. Pat. No. 6,454,099. All of these related applicationsand patents are incorporated herein in their entirety for all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to screens for vibratory shakers,screens for classifying and/or filtering material, such screens with oneor more ramped and/or raised portions over and/or through which materialto be treated flows, and vibratory separators with such screens. Incertain particular aspects, the present invention is directed to shaleshakers for treating drilling fluid with drilling solids and drilledcuttings entrained therein for recovering valuable drilling fluid forre-use in a drilling operation.

2. Description of Related Art

The related art section of each of the above-identified applications isincorporated here fully by reference.

The need for solids control in drilling mud used in hydrocarbon welldrilling is well known in the prior art. Drilling mud, typically amixture of clay and water and various additives, is pumped down througha hollow drill string (pipe, drill collar, bit, etc.) into a well beingdrilled and exits through holes in a drillbit. The mud picks up cuttings(rock) and other solids from the well and carries them upwardly awayfrom the bit and out of the well in a space between the well walls andthe drill string. At the top of the well, the solids-laden mud isdischarged over a shale shaker, a device which typically has a series ofscreens arranged in tiered or flat disposition with respect to eachother. The prior art discloses a wide variety of vibrating screens,devices which use them, shale shakers, and screens for shale shakers.The screens catch and remove solids from the mud as the mud passesthrough them. If drilled solids are not removed from the mud used duringthe drilling operation, recirculation of the drilled solids can createweight, viscosity, and gel problems in the mud, as well as increasingwear on mud pumps and other mechanical equipment used for drilling.

In some shale shakers a fine screen cloth is used with the vibratingscreen. The screen may have two or more overlying layers of screencloth. The prior art discloses that the layers may be adhered or bondedtogether; and that a support, supports, or a perforated or aperturedplate or frame may be used beneath the screen or screens. The screen isresiliently suspended or mounted upon a support and is caused to vibrateby a vibrating mechanism, e.g. an unbalanced weight on a rotating shaftconnected to the frame. Each screen may be vibrated by vibratoryequipment to create a flow of trapped solids on top surfaces of thescreen for removal and disposal of solids. The fineness or coarseness ofthe mesh of a screen may vary depending upon mud flow rate and the sizeof the solids to be removed.

Many screens used with shale shakers are flat or nearly flat (i.e.substantially two-dimensional). Other screens, due to corrugated,depressed, or raised surfaces are three-dimensional. U.S. Pat. Nos.5,417,793; 5,417,858; and 5,417,859 disclose non-flat screens for usewith shale shakers. These screens have a lower planar apertured platewith a multiplicity of spaced-apart apertures or openings therethrough.Undersides of troughs of undulating screening material are bonded to theapertured plate.

Vibrating screens have been employed for many years to separateparticles in a wide array of industrial applications. One commonapplication of vibrating screens is in drilling operations to separateparticles suspended in drilling fluids. The screens are mountedgenerally horizontally on a vibrating mechanism or shaker that impartseither a rapidly reciprocating linear, elliptical or circular motion tothe screen. Material from which particles are to be separated is pouredonto a back end of the vibrating screen, usually from a pan mountedabove the screen. The material generally flows toward the front end ofthe screen. Large particles are unable to move through the screenremaining on top of the screen and moving toward the front of the screenwhere they are collected. The smaller particles and fluid flows throughthe screen and collects in a pan beneath the screen.

A vibrating screen may be formed from one or more layers of wire mesh.Wire mesh is generally described with reference to the diameter of thewires from which it is woven, the number wires per unit length (called amesh count) and the shape or size of the openings between wires. Wiremesh comes in various grades. “Market” grade mesh generally has wires ofrelative large diameter. “Mill” grade has comparatively smaller diameterwires and “bolting cloth” may have the smallest diameter wire. The typeof mesh chosen depends on the application. The related art section ofeach of the above-identified applications and patents is incorporatedhere fully by reference.

FIG. 34A discloses one example of a typical prior art shaker system(e.g. as shown in U.S. Pat. No. 5,190,645). A well is being drilled by abit carried on a string of drill pipe as drilling mud is pumped by apump into the drill pipe and out through nozzles in the bit. The mudcools and cleans the cutters of the bit and then passes up through thewell annulus flushing cuttings out with it. After the mud is removedfrom the well annulus, it is treated before being pumped back into thepipe. The mud enters a shale shaker where the relatively large cuttingsare removed. The mud then enters a degasser where gas can be removed ifnecessary. The degasser may be automatically turned on and off, asneeded, in response to an electric or other suitable signal produced bya computer and communicated to degasser. The computer produces thesignal as a function of data from a sensor assembly associated withshale shaker. The mud then passes to a desander and (or a desilter), forremoval of smaller solids picked up in the well. The mud next passes toa treating station where, if necessary conditioning media, such asbarite, may be added. Suitable flow controls e.g. a valve, control theflow of media. The valve may be automatically operated by an electric orother suitable signal produced by the computer as a function of the datafrom sensor assembly. From the treatment station, the mud is directed toa tank from which a pump takes suction, to be re-cycled through thewell. The system shown in exemplary, and it will be understood thatadditional components of the same types (e.g. additional treatmentstations) or other types (e.g. centrifuges) could be included. Such ashale shaker or vibrator separator apparatus may employ any known screenor screens and may have a single screen or combination of two or morescreens, one above the other, as is well known in the art.

SUMMARY OF THE PRESENT INVENTION

The present invention discloses, in at least certain embodiments, ascreen assembly for a vibratory separator, the screen assembly having afirst screen portion having a first end and a second end spaced apartfrom the first end, a second screen portion adjacent the second end ofthe first screen portion, the second screen portion projecting down fromthe second end of the first screen portion. In one aspect such a screenassembly has a seal structure on an end of the second portion forsealingly abutting an end of another screen assembly.

The present invention discloses in at least certain aspects a screenassembly for a vibratory separator, the screen assembly including afirst screen portion having a first end and a second end spaced apartfrom the first end, a second screen portion adjacent the second end ofthe first screen portion, the second screen portion projecting down fromthe second end of the first screen portion. In certain aspects such ascreen assembly has a second screen portion having a seal structure forsealingly abutting an end of another screen assembly, and in oneparticular aspect the seal structure is a lip projecting from the secondend of the screen.

The present invention discloses, in at least certain embodiments, ascreen assembly for a vibratory separator, the screen assembly having afirst screen portion having a first end and a second end spaced apartfrom the first end, an optional a second screen portion adjacent thesecond end of the first screen portion and projecting down from thesecond end of the first screen portion, and at least one raised portionprojecting upwardly from the first screen portion. In certain methodsusing such a screen assembly, the raised portion has a top, material tobe screened (e.g., but not limited to, drilling fluid or “mud”) flowsover a top surface of the first screen portion, the material having atop surface, the top of the raised portion above the top surface of thematerial. In certain aspects the top of the raised portion is at leastone inch above the top surface of the material and in other aspects itis at least two inches above the top surface of the material.

The present invention discloses, in at least certain embodiments, ascreen assembly for a vibratory separator apparatus, the screen assemblywith at least two screening members, and the at least two screen membersconnected by sewing material (e.g., but not limited to thread,thread-like material, staples, and/or rivets). In such a screenassembly, the at least two screening members may be a plurality oflayers of screening material, and in one aspect, the plurality of layersof screening material includes at least one or two fine screen layersand a second coarse screen layer.

The present invention discloses a method to separate components of aflow including fluid with a vibratory separator apparatus, the methodincluding introducing the flow including fluid onto a screen assembly ofthe vibratory separator apparatus, the screen assembly having a firstscreen portion having a top surface and a first end and a second endspaced apart from the first end, the second screen portion projectingdown at an angle from the first screen portion, the first screen portionhaving first screening material, the second screen portion having secondscreening material at an angle to the first screen portion, the firstscreen portion adjacent the second screen portion so that a flowincluding fluid flowing from the top surface of the first screeningmaterial flows down onto the second screening material for separation offluid by the second screening material from the flow including fluid,and separating components of the flow including fluid with the firstscreen portion. In one aspect the method includes separating componentsof the flow including fluid with the second screen portion

The sewing material may be thread; thread-like material including butnot limited to, yarn, twine, string, rope and cord; rivets; and staplesor any other suitable material. The sewing material may be in a patternof spaced-apart items, knots or stitches over the surface of the screenmembers. One of the screen members may be a perforated plate.

In one particular embodiment of a screen assembly according to thepresent invention there are at least two screening members including atleast two or three layers of screening material and a base, the layersof screening material sewn together to form a combined screen, thecombined screen sewn to the base.

The present invention also provides, in at least certain embodiments, avibratory separator apparatus or shale shaker with a vibratory shakerdevice, a screen assembly mounted on the vibratory shaker device andwith at least two screening members, and the at least two screen membersconnected by sewing material.

What follows are some of, but not all, the objects of this invention. Inaddition to the specific objects stated below for at least certainpreferred embodiments of the invention, other objects and purposes willbe readily apparent to one of skill in this art who has the benefit ofthis invention's teachings and disclosures. It is, therefore, an objectof at least certain preferred embodiments of the present invention toprovide:

New, useful, unique, efficient, nonobvious screens; vibratory devices,apparatuses, and shale shakers with such screens; and methods for usingthe screens

Certain embodiments of this invention are not limited to any particularindividual feature disclosed here, but include combinations of themdistinguished from the prior art in their structures and functions.Additional aspects of the invention described below and which may beincluded in the subject matter of the claims to this invention. Thoseskilled in the art who have the benefit of this invention, itsteachings, and suggestions will appreciate that the conceptions of thisdisclosure may be used as a creative basis for designing otherstructures, methods and systems for carrying out and practicing thepresent invention. The claims of this invention are to be read toinclude any legally equivalent devices or methods.

The present invention recognizes and addresses the previously-mentionedproblems and long-felt needs and provides a solution to those problemsand a satisfactory meeting of those needs. To one skilled in this artwho has the benefits of this invention's realizations, teachings,disclosures, and suggestions, other purposes and advantages will beappreciated from the following description of preferred embodiments,given for the purpose of disclosure, when taken in conjunction with theaccompanying drawings. The detail in these descriptions is not intendedto thwart this patent's object to claim this invention no matter howothers may later disguise it by variations in form or additions offurther improvements.

BRIEF DESCRIPTION OF THE DRAWINGS

A more particular description of embodiments of the invention brieflysummarized above may be had by references to the embodiments which areshown in the drawings which form a part of this specification. Thesedrawings illustrate certain preferred embodiments and are not to be usedto improperly limit the scope of the invention which may have otherequally effective or legally equivalent embodiments.

FIG. 1A is a top view of a screen plug according to the presentinvention. FIG. 1B is a side view of an embodiment of a plug as in FIG.1A. FIG. 1C is a side view of an embodiment of a plug as in FIG. 1A.

FIG. 2A is a top view of a screen plug according to the presentinvention. FIG. 2B is a cross-section view along line 2B—2B of FIG. 2A.FIGS. 2C, 2D are side views of an embodiment of a plug as in FIG. 2A.

FIG. 3A is a top view of a screen plug according to the presentinvention. FIG. 3B is a cross-section view along line 3B—3B of FIG. 3A.FIG. 3C is a side view of an embodiment of a plug as in FIG. 3A. FIG. 3Dis a side view of an embodiment of a plug as in FIG. 3A. FIG. 3E is aside view of an embodiment of a plug as in FIG. 3A. FIG. 3F is a sideview in cross-section of a fastener for the plug of FIG. 3F.

FIG. 4A is a top view of a screen according to the present invention.FIG. 4B is an end view of the screen of FIG. 4A.

FIG. 5A is a top view of a screen according to the present invention.FIG. 5B is an end view of the screen of FIG. 5A.

FIG. 6A is a perspective view of a strip support according to thepresent invention. FIGS. 6B, 6D are end views of the strip support ofFIG. 6B. FIG. 6C is a top view of the strip support of FIG. 6A.

FIGS. 7A, 7E are top views of a strip support according to the presentinvention. FIG. 7B is a perspective view of the strip support of FIG.7A. FIGS. 7C, 7D are end views of the strip support of FIG. 7B.

FIG. 8 is a top schematic view of a screen assembly according to thepresent invention.

FIG. 9 is a side cross-section view of a screen assembly according tothe present invention.

FIG. 10A is a side cross-section view of a screen assembly according tothe present invention. FIG. 10B is a side cross-section view of a screenassembly according to the present invention.

FIG. 11A is a side cross-section view of a screen assembly according tothe present invention. FIG. 11B is a top view of the screen assembly ofclaim 11A.

FIG. 12A is a side cross-section view of a screen assembly according tothe present invention. FIG. 12B is a top view of the screen assembly ofclaim 11A.

FIG. 13 is a side cross-section view of a plug according to the presentinvention.

FIG. 14 is a side cross-section view of a plug according to the presentinvention.

FIG. 15A is a bottom view of a plug according to the present invention.FIG. 15B is a side view of the plug of FIG. 15A.

FIG. 16A is a bottom view of a plug according to the present invention.FIG. 16B is a side view of the plug of FIG. 15A.

FIG. 17A is a top view of a screen assembly according to the presentinvention. FIG. 17B is an end view of the screen assembly of FIG. 17A.FIG. 17C is an end view of an elongated plug of the screen assembly ofFIG. 17A. FIGS. 17D and 17E are end views of alternative elongated plugembodiments.

FIGS. 18A–18D are top views of prior art perforated plates.

FIG. 19A is a perspective view of a strip system according to thepresent invention. FIG. 19B is a cross-section view along line 19B—19Bof FIG. 19A. FIG. 19C is a cross-section view along line 19C—19C of FIG.19B. FIG. 19D is a cross-section view of a system as in FIG. 19A.

FIG. 20A is a cross-section view of a screen support member according tothe present invention. FIG. 20B shows a side cross-section view of thesupport of FIG. 20A.

FIG. 21A is a cross-section view of a screen support member according tothe present invention. FIG. 21B shows a side cross-section view of thesupport of FIG. 21A.

FIG. 22A is a cross-section view of a screen support member according tothe present invention. FIG. 22B shows a side cross-section view of thesupport of FIG. 22A. FIG. 22C is a cross-section view of a screensupport member according to the present invention.

FIG. 23A is a top view of a screen according to the present invention.FIG. 23B is a view along line 23B—23B of FIG. 23A. FIG. 23C is a viewalong line 23C—23C of FIG. 23B. FIG. 23D is a cross-section view of ascreen according to the present invention.

FIG. 24A is a perspective view of a screen according to the presentinvention. FIG. 24B is a bottom view, FIG. 24C a top view, FIG. 24D aside view, FIG. 24E a side view, and FIG. 24F an end view of the screenof FIG. 24A.

FIGS. 25A–25E are cross-section views of screen ramp portions accordingto the present invention.

FIGS. 26–28 are top views of screens according to the present invention.

FIGS. 29A and 29B are cross-section views of screen ramp portionsaccording to the present invention.

FIGS. 30A and 30B are cross-section views of screen ramp portionsaccording to the present invention.

FIG. 31 is a side view of a screen according to the present invention.

FIG. 32A is a top view of a screen according to the present invention.FIG. 32B is a cross-section view along line 32B—32B of FIG. 32A.

FIG. 33 is a perspective view of a system according to the presentinvention.

FIG. 34A is a schematic view of a prior art system. FIG. 34B is aschematic view of a system according to the present invention.

FIG. 35A is a top view partially cut-away of a screen according to thepresent invention. FIG. 35B is an exploded view of the screen of FIG.35C. FIG. 35C is an end view of the screen of FIG. 35A. FIG. 35D is anenlargement of part of the screen of FIG. 35C.

FIG. 36 is an end view in cross section of an alternative embodiment ofthe screen of FIG. 35A.

FIG. 37 is an end view of a screen according to the present invention.

FIG. 38A is a top view of a screen according to the present invention.FIG. 38B is an exploded view and FIG. 38C is an end view of the screenof FIG. 38A. FIG. 38D is an enlargement of a portion of the screen shownin FIG. 38C. FIG. 38E is an end view that shows an alternative structurefor the screen of FIG. 38A.

FIGS. 39A, 39B and 40 are perspective views of screen assembliesaccording to the present invention.

FIG. 41A presents a perspective view of a variety of componentsaccording to the present invention for screen assemblies according tothe present invention. FIG. 41B presents end views of the components ofFIG. 41A.

FIG. 42A is a perspective view of a variety of components according tothe present invention for screen assemblies according to the presentinvention. FIGS. 42B and 42C present cross-section views of parts of thescreen assembly of FIG. 42A. FIGS. 42D and 42E present alternativeconfigurations for screen components according to the present invention.

FIG. 43 is a perspective views of screen assemblies according to thepresent invention.

FIGS. 44A, 45A, 46A and 47A present a side view of a piece of material,screen or mesh which is formed into the screen components shown,respectively in FIGS. 44B, 45B, 46B, 47B and 47C.

FIG. 48A is a side view of a screen component according to the presentinvention. FIG. 48B shows the component of FIG. 48A on a screenaccording to the present invention.

FIG. 49 is a side view of a screen component (as in FIG. 48A) on ascreen according to the present invention and

FIGS. 50A–50C are side view of a screen according to the presentinvention.

FIG. 51A is a top view of a screen assembly according to the presentinvention. FIG. 51B is a cross-section view of the screen assembly ofFig.

FIG. 52 is a cross-section view of a screen assembly according to thepresent invention.

FIG. 53 is a cross-section view of a screen assembly according to thepresent invention.

FIG. 54 is a perspective view of a channel member for a screen accordingto the present invention.

FIGS. 55A and 55B are cross-section views of channel members for ascreen according to the present invention.

FIG. 55C presents perspective views of channel members for a screenaccording to the present invention.

FIG. 56 is a top view of a screen assembly according to the presentinvention.

FIGS. 57 and 58 are cross-section views of parts of the screen of FIG.56.

FIG. 59 is a top view of a screen assembly according to the presentinvention.

FIGS. 60, 61, 62, 65 and 66 are cross-section views of screen assembliesaccording to the present invention.

FIG. 63 is a top view of a screen assembly according to the presentinvention.

FIG. 64 is a top view of a screen assembly according to the presentinvention.

FIGS. 67A and 67B are schematic views showing a method according to thepresent invention for making screen assemblies according to the presentinvention.

FIG. 68 is a schematic view showing a method according to the presentinvention for making screen assemblies according to the presentinvention.

FIG. 69 is a perspective view of a screen assembly according to thepresent invention.

FIG. 70A is a top schematic view of part of a screen assembly accordingto the present invention. FIG. 70B is a side view of the screen assemblyof FIG. 70A.

FIG. 71A is a top schematic view of part of a screen assembly accordingto the present invention. FIG. 71B is a side view of the screen assemblyof FIG. 71A.

FIG. 72 is a top view of a screen assembly according to the presentinvention.

FIG. 73 is a top view of a screen assembly according to the presentinvention.

FIG. 74 is a side view of a ridge of three-dimensional screen assemblyaccording to the present invention.

FIG. 75A is a top view of screen assembly according to the presentinvention. FIG. 75B is an end view of the screen assembly of FIG. 75A.

FIG. 76A is a perspective view of a screen assembly according to thepresent invention.

FIG. 76B is a perspective view of a basket with screen assemblies as inFIG. 76A.

FIGS. 76C–76E are side views of screen assemblies according to thepresent invention.

FIG. 77A is a perspective view of a screen assembly according to thepresent invention.

FIG. 77B is a perspective view of a basket with screen assemblies as inFIG. 77A.

FIGS. 78–82 are perspective views of screen assemblies according to thepresent invention.

FIGS. 83–85 are perspective views of raised portions of screenassemblies according to the present invention.

FIGS. 86–88 are bottom views of screen assemblies according to thepresent invention.

FIG. 89A is a top view and FIG. 89B is an end view of a screen accordingto the present invention.

FIG. 90 is a perspective view of a screen according to the presentinvention.

DESCRIPTION OF EMBODIMENTS PREFERRED AT THE TIME OF FILING FOR THISPATENT

As shown in FIG. 1A, a plug 160 according to the present invention has abody 161 and a mesh 162 formed integrally thereof. It is within thescope of this invention for the mesh to be a wire mesh or meshes (orscreens) secured to the body 161 or wire mesh over the integral mesh162. In certain aspects the plug 160 is a single piece member made ofplastic or urethane.

In the embodiment of FIG. 1B, the plug 160 has an upper member 163spaced apart from a lower member 164 by a snap recess 165 which is sizedto correspond to an edge of a screen opening so that the plug 160 may besnapped into and then held in the screen opening.

In the embodiment of the plug 160 in FIG. 1C, an upper member 166 isdisposed above a lower member 167. The lower member 167 is sized to fitin an opening of a screen. The plug 160 may be held in place in a screenopening by a friction fit and/or with a suitable glue, adhesive, orepoxy. Velcro™ material at plug edges and on opening edges may be usedto releasably secure any plug herein at or in an opening. Plugs ofdifferent screening material or mesh or mesh size may be used indifferent screen areas; e.g., but not limited to plugs with a 40 mesh atback edge of a screen and plugs with a 100 mesh at a front end of thescreen.

As shown in FIGS. 2A, 2B and 2C, a plug 170 according to the presentinvention has a body 171 and a mesh 172 formed integrally thereof. It iswithin the scope of this invention for the mesh to be any known mesh orscreen, meshes or screens, or combination thereof, including but notlimited to a layer or layers of plastic or synthetic mesh or a piece orpieces of perforated plastic or synthetics (bonded together, unbonded,or bonded at intermittent points) or a wire mesh secured to the body171. In certain aspects the plug 170 is a single piece member made ofplastic or urethane.

In the embodiment of FIG. 2A, the plug 170 has an upper member 173spaced apart from a lower member 174 by a snap recess 175 which is sizedto correspond to an edge of a screen opening so that the plug 170 may besnapped into and then held in the screen opening.

In the embodiment of the plug 170 in FIG. 2D, an upper member 176 isdisposed above a lower member 177. The lower member 177 is sized to fitin an opening of a screen. The plug 170 may be held in place in a screenopening by a friction fit and/or with a suitable glue, adhesive, orepoxy.

As shown in FIGS. 3A, 3B and 3C, a plug 180 according to the presentinvention has a body 181 and a mesh 182 formed integrally thereof. It iswithin the scope of this invention for the mesh to be a wire meshsecured to the body 181. In certain aspects the plug 180 is a singlepiece member made of plastic or urethane.

In the embodiment of FIG. 3A, the plug 180 has an upper member 183spaced apart from a lower member 184 by a snap recess 185 which is sizedto correspond to an edge of a screen opening so that the plug 180 may besnapped into and then held in the screen opening.

In the embodiment of the plug 180 in FIG. 3D, an upper member 186 isdisposed above a lower member 187. The lower member 187 is sized to fitin an opening of a screen. The plug 180 may be held in place in a screenopening by a friction fit and/or with a suitable glue, adhesive, orepoxy.

FIG. 3E shows an embodiment of the plug 180 with an upper body 188 and alower body 189 with threads 190 thereon. A fastener 191 (FIG. 3F) withinternal threads 192 threadedly mates with the lower body 189 toremovably attach the plug 180 in a screen opening. Internal threads maybe used on the plug 180 with an externally threaded fastener.

FIG. 4A shows a screen 330 according to the present invention with aplurality of ridges with ridge tops 332 connected to ridge sides 333with bottom member 334 between adjacent ridge sides 333. The ridge tops332 have a plurality of openings 335 each with a plug 336 thereinaccording to the present invention. The ridge sides 333 have a pluralityof openings 337 each with a plug 338 therein according to the presentinvention. The bottom member 334 has one or a plurality of at least twoor more openings each with a plug 339 therein according to the presentinvention. A plate 340 has the ridge tops 332, ridge sides 333 andbottom members 334, each with their respective openings. It is withinthe scope of this invention for some or substantially all (e.g. thetotal minus one, two, three, four, five, or up to twenty) of theopenings in the plate 340 to be covered with screen, screens, mesh ormeshes in any combination applied and secured in any known manner or inany manner disclosed herein. It is within the scope of this inventionfor any opening in the plate 340 to have a plug permanently or removablydisposed therein or for such a plug to be emplaced in any opening torepair damaged screen or to replace a previously used plug. Any plugdisclosed herein may be used with the screen 330. The plugs 342 are likethe plugs of FIGS. 1C, 2D, 3D or 3E. It is within the scope of thisinvention for the screen 330 to have any number of desired ridges 332 ofany suitable dimensions with corresponding ridge sides 333 and bottommembers 334, or with interconnected ridges having no bottom membertherebetween. Alternatively, pointed corrugations may be used with noflat top and no flat bottom or with a flat bottom and pointed top. Sucha screen (and any screen or screen assembly disclosed herein) may beused on a frame; on a flat perforated plate; on one or more bracesand/or strip supports (flat and/or corrugated; and corrugated tocorrespond to the shape of the screen 330's shapes); on a combinationthereof; and/or with upturned side edges or other connection apparatusfor connection to a vibratory separator or shale shaker.

It is within the scope of this invention for the plugs of FIGS. 2A–2Dand 3A–3E (and any plug disclosed herein) to be circular, oval, orsquare, rectangular, triangular, regular polygonal, polygonal elliptical(as viewed from above) or to be elongated as disclosed below. It iswithin the scope of this invention for mesh or meshes on or formedintegrally of any plug herein (described above or below) to be orientedand emplaced on a screen either parallel to or normal to the directionof flow of material onto the screen for dewatering or classifying asdesired. It is within the scope of this invention to provide a plug(described above or below) with both mesh or meshes formed integrallythereof and mesh or meshes applied thereunder or thereover. Upper plugparts may be made of plastic (or urethane) with lower parts made ofmetal, or vice versa. The plug body may be plastic or metal with plasticand/or wire mesh bonded to it. Different plugs may be used in the samescreen. Plugs can be any desired size. In one aspect plugs range from asmallest width of about 0.5 inches to one foot wide, or more and from alength of 0.5 inches to several feet. In one aspect plugs with differentmesh or screen than other plugs are used in the same screen to provide adifferent classification function in one screen. In one aspect plugs ofuniform size with similar or dissimilar mesh or screen are used.

FIG. 5A shows a screen 350 according to the present invention with aplurality of openings 351 and 352 in a plate 360. Plugs 353 are securedin some of the openings 351 and a plug 354 is in one of the openings352. Mesh (shown partially in FIG. 5A) covers substantially all of thetops of the plugs 353 and 354. Screen 355 covers openings that are notplugged. Screen 355 may be any known screen, screens, mesh, or meshesapplied to the plate 360 in any known manner or any manner disclosedherein. The plate 360 may be any known plate, flat or corrugated.

FIG. 6A shows a support strip 370 according to the present inventionwith a body 371, ends 372 and upturned fingers 373, 374. In one aspectthe strip 370 is metal (e.g. but not limited to carbon steel orstainless steel), and the fingers are upturned following a cut 375 inthe body 371 and then a cut to separate the fingers. These cuts are madeand sized, in one aspect, so that the fingers are sized and positionedto correspond to raised portions of a corrugated screen or of acorrugated plate. The strip 370 can be used as any strip disclosedherein or in pending co-owned application U.S. Ser. No. 08/786,515 filedon Jan. 21, 1997 entitled “Screen For Shale Shaker” incorporated fullyherein for all purposes. Alternatively, the strip 370 can be a moldeditem made as shown in FIGS. 6A–6C. It is within the scope of thisinvention to have a strip with three, four, five or more sets ofupturned fingers and, in one aspect, to have a set of fingers for eachraised portion of a plate and/or screen used with the strip. It iswithin the scope of this invention to use any desired number of stripswith a plate and/or screen. One or more sets of fingers 373, 374 may beused on a strip with one or more fingers 385 of the strip of FIG. 7A.FIG. 6D shows an alternative embodiment of the strip 370 with aninternal support 377 between fingers 373, 374. Such supports 377 may beglued in place to the interior surfaces of the fingers 373, 374. If thestrip 370 is metal and the supports 377 are metal, they may be glued,sintered, or welded in place. The supports 377 (and strip 370) may bemade of materials as described below for the supports and strips inFIGS. 19A–23D.

FIGS. 7A–7C disclose a support strip 380 for a screen and/or plate whichhas a body 381 (in one aspect made of metal) with ends 382 and a cut 383which has fingers 385. As shown in FIGS. 7B and 7C, the fingers 385 areupturned and have a top curved portion 384. In one aspect the top curvedportion 384 corresponds in shape to a curved portion of a corrugatedplate and/or screen used with one or more of the strips 380.Alternatively the strip 380 can be made of one integral plastic piece.Any desired number of fingers 385 may be provided. FIGS. 7D and 7E showan alternative embodiment of the strip 380 with an internal support 387beneath each finger 385. The supports 387 have an end portion 388extending over a top of the strip 380. The supports 387 may be securedto the interior surface of the fingers 385 and/or secured to or fastenedto the strip 380. The supports 387 as shown do not extend downward tothe lowest extent of the bottom of the strip 380, although this would bewithin the scope of the invention. The supports 377, 387 may be one or aseries of fluid flow holes therethrough—as may any support in FIGS.19A–23D. Any support disclosed herein may be fastened to a strip and/orscreen and/or plate with one or more fasteners and/or with Velcro™material.

The present invention discloses a method for making a screen assembly inwhich a perforated plate is sandblasted and/or washed with any suitabledegreaser and/or soap. Any suitable perforated plate may be used. In oneparticular embodiment the perforated plate has round holes about ¼ inchin diameter or square holes with a diagonal measurement of about ¼ inchwhich have centers that are about 0.030 inches apart and that areseparated from each other by about 0.050 inches of plate. Alternativelyholes with a ⅜ inch, or ½ inch diameter may be used. The plate, incertain aspects, is made of carbon steel, stainless steel, or plastic.The holes, in one aspect, are at a 45° angle to the direction of fluidflow across the plate. If desired, the plate can be sandblasted orsanded.

The plate is heated to about 450° F. (in an oven or heat press) and isthen dipped, preferably while positioned horizontally, into a fluidizedbed of epoxy, (or other suitable adhesive) to coat the plate with meltedepoxy powder in the bed. Heat in the plate permits the epoxy powder tobond to it in a semi-cured state. In another aspect powdered nylon, (orpowdered polyester, or any suitable powderized coating) is coated ontothe plate using a fluidized bed. In one aspect the epoxy is about 15 to30 mils thick and in another aspect is about 20 mils thick on top of theplate and about 5 mils thick on the sides and bottom.

One, two, three, four or more layers of wire mesh are then cut to coverthe pattern of perforations on the screen plate (in one aspect wider andlonger than the coated screen plate), in one aspect mesh of 2 mesh to500 mesh. The wire mesh and screen plate are placed on top of anon-stick panel (e.g. a panel made of 20 gauge steel with a Teflon (™)coating is applied to the panel; alternatively a 20 gauge steel sheetwith a 20 mil thick sheet of Teflon (™) material on it may be used). Thenow non-stick panel acts as a tray for sliding the plate/meshcombination into an oven and the panel prevents the screen plate coatingfrom sticking to the oven. Due to the Teflon (™) coating the platesurface adjacent to the wire mesh, the screen plate and wire mesh do notbond to the panel. The screen plate, alternatively, may be placed on topof the mesh or meshes. A second non-stick panel is then placed over thefirst plate/mesh/panel combination. This second panel non-stickingsurface is adjacent to the plate. In one aspect this second panel has asheet of self-adhesive Teflon (™) material on its lower side facing themesh on the plate. Instead of Teflon (™) material, any material may beused which will prevent the epoxy (nylon, polyester, etc.) from stickingto the panels. The two panels may be fastened together to providepressure to facilitate encapsulation of the mesh by molten epoxy.

The sandwich of panels, plate, and mesh is placed in an oven, e.g. for 6to 8 minutes at 340° F. to cure the epoxy. The cured screen plate isremoved from the oven and the mesh and epoxy are cut flush with thesides of the screen plate. It is known in the art to thus prepare aplate/mesh combination. However, the inventors are unaware of any priorart teaching: the re-introduction of the plate/mesh back into an oven;the re-heating of the plate/mesh; or corrugating a re-heated combinationof plate/mesh.

The plate with the mesh may then be corrugated or, alternatively, it isfirst placed back in the oven for about 2 minutes at about 450° F. Whilestill hot, the plate is removed from the oven and corrugated (e.g. usinga press brake). In one aspect a plate about 36 inches wide and about 47inches long after corrugations has corrugations with ridges that areabout an inch high. In one preferred embodiment the plate with the meshand cured epoxy is at a temperature of at least about 250° F. until thecorrugating operation is finished. With more flexible cured materials,e.g. nylon, it is not critical to maintain the relatively hightemperature level of the plate during the corrugation operation.Alternatively, the plate is not corrugated.

The resulting screen assembly may be attached to a frame or it may beprovided with upturned opposed edges for connection to a separator orshaker. In one aspect Velcro (™) material on the screen assembly is usedwith mating Velcro (™) material on a frame or on a separator or shakerto releasably attach the screen assembly thereto. In another aspect thescreen assembly is thus connected to one or more support strips (e.g.but not limited to, any support strip described herein).

In one aspect such a screen assembly is placed on a frame coated withepoxy and the two items are held together between Teflon (™) materialsheets. This combination is then cooked at about 450° F. for about 8 to15 minutes to cure the epoxy and secure the screen assembly to theframe.

In one aspect a corrugated screen assembly as described above has thespaces below ridges capped or plugged at each end of the screenassembly.

FIG. 8 shows schematically a screen 450 with a plurality of screeningplugs or modules 451, 452, 453 that are removably secured incorresponding openings 454 in a plate 456. Each module may be any size.With modules larger than those shown (e.g. up to a largest dimension of6, 8, 12 or more inches or several feet; and in one aspect a screen withrelatively few modules e.g. as in FIG. 8) there are fewer modules overthe plate surface and with smaller modules (e.g. down to a largestdimension of about ½ inch) there are more modules over the platesurface. In one aspect the modules 451 have a relatively coarse metalmesh, e.g. 150 mesh screen; the modules 452 have a coarser mesh, e.g. 80mesh; and the modules 453 have a fine mesh, e.g. 200 mesh, with the flowof fluid to be treated from the fine to the coarse modules (right toleft in FIG. 8). Alternatively this pattern can be reversed; all themodules may have a substantially similar mesh; or any and all modulesmay have a combination of meshes thereon, including screens in layers ofdifferent mesh and/or screens or meshes made of different material, e.g.but not limited to carbon steel, stainless steel, Teflon (™) material,plastic, and/or urethane.

It is within the scope of this invention to provide any plug or moduledisclosed herein initially with no holes, perforations, or openingstherethrough and then, e.g. later at a job site, to perforate the plugor module with the desired number and desired size openings, holes, orperforations or combination thereof. Such openings (and holes oropenings for any plug or module disclosed herein) may be normal to thedirection of the flow of fluid flowing above the hole, etc. (e.g. forclassification) or at an angle other than perpendicular to suchdirection of flow (e.g. for dewatering to remove a large, preferablymaximum, amount of liquid from a product).

With respect to the screen of FIG. 8 (or any other screen disclosedherein) it is within the scope of this invention for any plug or module,or any group thereof, to be fashioned for dewatering and/or forclassification. A single screen may, therefore, have an area primarilyfor dewatering a product flowing thereacross and an area for classifyingcomponent materials of the product. Plugs and modules disclosed hereinmay be made of metal, plastic, fiberglass, cermet, urethane, KYNAR,polymeric material, BUNA N, Teflon (™) material, or polyvinylidenefluoride. In one aspect a screen is provided with plugs or modules madeof urethane (or similar material) for a high wear area (e.g. at an areaof the initial introduction of a slurry to a first screen, the areawhich first encounters fluid and/or product to be treated); and a lowerwear area with plugs or modules with metal wire mesh.

Square plugs or similar plugs fitted with woven mesh (e.g. rectangularwoven mesh) can be fitted to provide a screen for classifying ordewatering. With rectangular openings, in one aspect flow parallel to along opening is used for dewatering and flow perpendicular to a longopening is used for classification.

FIG. 9 shows a screen assembly 460 with a plate 462 having holes 463therethrough. A plug 464, 465, or 466 is removably secured in each hole463. The plugs convert the plate into a 3-D corrugated screen assembly.It is within the scope of this invention for the plugs to have anydesired shape and size to make a screen assembly with ridges of anyshape and size—the ridges being part of the plugs. The plugs may bediscrete separate items with a plurality of them spaced apart or theymay be elongated members, e.g. two, four, twelve, twenty four, thirty,thirty six or more inches long and one, two, three, four or more incheswide.

The plug 464 has openings 467. Any number of openings of any desiredsize may be used. A mesh 468 covers the exposed surface of the plug 464.The plate 462 has optional openings 469 (any desired number and in anydesired pattern) which may be sized for dewatering, separation, orclassifying.

The plugs 465 have openings 469 and have no mesh thereon. The plug 466has two mesh layers 470 and 471 and holes 472. Any combination of anymesh made of any material may be used on the plugs 464, 465, 466.Grooves 475 permit the plugs to be snapped into the holes 463.Alternatively the plugs can be permanently or semi-permanently bonded tothe plate. Failed or damaged plugs may be replaced with little or noloss of screening area.

FIG. 10A shows a screen assembly 480 according to the present inventionwith a plate 482 having holes 481 therethrough and thereacross. A groove484 permits plugs 485 to be snapped into the holes 481. A top perforatedplug body 483 projects above the plate surface and a bottom perforatedplug body 488 projects below the plate surface. Perforations 486 in thetop perforated plug body may be similar to or different fromperforations 487 in the bottom perforated plug body in size anddisposition and they may be angled differently. Top and bottom plugbodies may be made of similar or different material and they may haveone or more meshes (metal or otherwise thereon). As with the plugs ofFIG. 9 and others disclosed herein, the plugs 485 may be any desiredsize, length, width, and cross-sectional shape.

FIG. 10B shows a screen assembly 490 with plugs as in FIG. 9 above a topsurface of the plate 462 and bottom plug bodies like those of the plugs485 (FIG. 10A). Holders 491 hold the bottom plug bodies on the plate462. The holders 491 use the grooves 484 as is shown in FIG. 10A. Thesections of the plate 462 between plugs may have holes or openingstherethrough. The holes 463 in the plate 462 may be sized and configuredas any opening or hole disclosed herein, including but not limited to anarray of adjacent holes or openings (square, hexagonal, circular,triangular, rectangular) extending across the entire surface of theplate 462 or a series of relatively long openings extending from oneside of a square or rectangular plate 462 to the other so that acorrugated screen is formed with both upper and lower corrugatedsurfaces defined by the plugs, the plugs extending for substantially thewhole length of the relatively long openings.

FIGS. 11A and 11B show a screen assembly 630 according to the presentinvention with a plate 631 (shown partially) having a plurality ofopenings 632 thereacross. The openings 632 may initially be covered byone or more meshes and/or screens (as with all plates disclosed herein)or, alternatively all the openings 632 may have a plug 634 therein (aswith all plates disclosed herein). Also, a plug 634 may be used torepair damaged mesh/screen over an opening with little or no loss ofscreening area. The plug 634 has a tapered body 635 corresponding to atapered surface of the openings 632 and a lower lip 636 that permits theplug to be snapped into the openings 632 and held in the openings 632.The plug 634 has holes 637 extending therethrough. Alternatively theplugs 634 may be solid or may have more or less holes of larger orsmaller diameter than those shown. The plug 634 as shown in FIG. 11B iselliptical as viewed from above; however it is within the scope of thisinvention to use any suitable shape, including but not limited tosquare, circular, triangular, hexagonal, polygonal, regular polygonal orrectangular. Also, a mesh, meshes, screen, and/or screens may be appliedon the top surface of the plugs 634. It is critical for certainparticular embodiments of the screen assembly 630 that the top surfaceof the plugs 634 is substantially flush with the top surface of theplate 631 (or with mesh etc. on top of the plate). Materials disclosedherein may be used for the plugs and plate.

FIGS. 12A and 12B show a screen assembly 640 according to the presentinvention with a plate 641 (shown partially) having a plurality ofopenings 642 thereacross. The openings 642 may initially be covered byone or more meshes and/or screens (as with all plates disclosed herein)or, alternatively all the openings 642 may have a plug 644 therein (aswith all plates disclosed herein). Also, a plug 644 may be used torepair damaged mesh/screen over an opening. The plug 644 has a body 645and a groove 646 that permits the plug to be snapped into the openings642 and a bead 649 on the plate 641 to enter into the groove 646 to holdthe plugs 644. The plug 644 has holes 647 extending therethrough.Alternatively the plugs 644 may be solid or may have more or less holesof larger or smaller diameter than those shown. The plug 644 as shown inFIG. 12B is circular as viewed from above; however it is within thescope of this invention to use any suitable shape, including but notlimited to square, circular, elliptical, hexagonal, polygonal, regularpolygonal, triangular, or rectangular. Also, a mesh, meshes screen,and/or screens may be applied on the top surface of the plugs 644. It iscritical for certain particular embodiments of the screen assembly 640that the top surface of the plugs 644 is substantially flush with thetop surface of the plate 641 (or with mesh etc. on top of the plate).Materials disclosed herein may be used for the plugs and plate.

FIG. 13 shows a plug 650 according to the present invention with a body651 and a top convex surface 652. A series of holes 653 extend throughthe plug 650. The plug 650 may be any desired size or shape.

FIG. 14 shows a plug 660 according to the present invention with a body661, a top convex surface 662, and a mesh 668 thereon. A series of holes663 extend through the plug 660. The plug 660 may be any desired size orshape. The holes 653 (FIG. 13) and holes 663 (FIG. 14) may be anydiameter and there may be any desired number of them.

FIGS. 15A and 15B show a plug 670 according to the present inventionwith a body 671 and a series of holes 673 extend therethrough. The plug670 may be any desired size or shape. The plug 670 is made of flexiblematerial and has an expansion ring 675 therein that pushes the plugsides outwardly to facilitate maintenance of the plug 670 in position ina plate opening and/or put the plug's mesh or meshes in tension. A meshor screen 675 is on top of the plug 670.

FIGS. 16A and 16B show a plug 680 according to the present inventionwith a body 682. A series of holes 683 extend through the plug 680. Theplug 680 may be any desired size or shape. The plug 680 is made offlexible material and has expansion springs 684 and 686 that push theplug sides outwardly to facilitate maintenance of the plug 680 inposition in a plate opening and/or put the plug's mesh or meshes intension. One, two, three or more springs may be used. Meshes 681 and 688are secured on the plug 680.

FIGS. 17A and 17B show a screen assembly 500 according to the presentinvention with a perforated plate 502 having perforations 504 extendingtherethrough from top to bottom. Any number and size perforations may beemployed in any desirable pattern or positioning on the plate 502.Dovetail recesses 506 extend across the plate 502. Holes 505 extend fromthe recesses through the plate 502. A corresponding dovetail base of anelongated hollow plug 510 is held in each dovetail recess 506. Each plug510 has a series of perforations or holes 508 therethrough and one ormore bottom holes 509. Any number and size holes may be employed in anydesired pattern or positioning on the plugs 510. The plugs 510 may beheld tightly in the recesses 506 with a tight friction fit and/or withwelding or epoxy. In one aspect the plugs 510 are removably insertedinto the dovetail recesses 506 for easy replacement and/or repair. Anyhole in a plug 510 may be repaired with a plug as previously describedabove for repairing damaged or torn mesh or screen. The perforations 504and/or the holes 508 may be covered with any known mesh, meshes, screenor screens, bonded or unbonded, in any combination or layers.

FIG. 17C shows one of the plugs 510.

FIG. 17D shows an alternative embodiment of an elongated hollow plug 520according to the present invention that has a body 522, holes 524therethrough, a base 526 with holes 528 therethrough and a dovetailportion 529 through which the holes 528 also extend. To enhance sealingof the plug/plate interface, a seal bead 521 is provided along each sideof the plug along its entire length. Alternatively such a seal membermay be formed of or secured to the plate with which the plug 520 isused. The seal bead or member may be plastic, rubber, or any knownsuitable sealing material. Such a bead may also serve to stabilize theplug in place on the plate.

FIG. 17E shows an alternative elongated solid plug 530 with a body 532having a series of holes 534 therethrough and a dovetail base 536. Amesh or screen 538 is secured over the plug body 532 covering the plugon its top surface. Fluid to be treated flows through the screen 538 andthrough the holes 534. Two or more meshes and/or screens may be used.

FIGS. 18A–18D show known perforation patterns for plates used withscreens which may be used with plates and/or screen assemblies accordingto the present invention. The direction of fluid flow on the plates ofFIGS. 18A–18D may be from top to bottom (as viewed in the Figures) orside to side (as viewed in the Figures).

Pending U.S. application Ser. Nos. 08/598,566 and 08/786,515, identifiedabove, are incorporated herein in their entirety for all purposes.

FIG. 19A shows a screen frame 700 according to the present invention. Inone aspect the frame 700 is made from a single sheet or frame piece fromwhich areas 702 are removed, e.g. but not limited to by an appropriatesaw or laser, to form outer sides 703, 704, 705, 706 and cross strips707 and cross strips 708. Each cross strip 708 has two raised portionsor humps 709. It is within the scope of this invention for any of thestrips 707, 708 to have one, two, three, four five or more humps 709.

As shown each hump 709 has an internal support 710 therebeneath. Thesupports 710 are secured to a strip's underside by any suitable means,including, but not limited to, glue, adhesives, epoxy, sintering, andwelding. The strips 707, 708 and the supports 710 may be made of anysuitable metal, plastic, fiberglass, or composite material.

As shown in FIGS. 19B and 19C the inner surface of a top of the raisedportion or hump 709 is spaced apart from a top surface of the supports710 to facilitate fluid flow over and around the supports 710.

As discussed below, the strips 707, 708 and/or supports 710 may have aseries of fluid flow holes therethrough. As shown in FIG. 19D a hump 711(like the humps 709, FIG. 19B) has a series of fluid flow holes 712therethrough and a support 713 (like the supports 710, FIG. 19B) has aseries of fluid flow holes 714 therethrough.

FIGS. 20A and 20B shows a hump 715 (like the humps 709, 711) on a strip716. The strip 716 has a series of fluid flow holes 719 therethrough,including holes through the hump 715. An internal support 717 with aseries of fluid flow holes 718 therethrough is substantially as wide asthe strip 716.

FIG. 21A shows a hump 720 (like the humps in FIGS. 19B, 19D, 20A) of astrip 721 (like the strips 708, 716) has an internal support 722; butthe support 722 viewed in cross-section as in FIG. 21A, occupiessubstantially all of the space under the hump 720 when viewed this way.The support 722 and/or hump 720 may have a series of fluid flow holestherethrough. The support 722, as is true of the supports in FIGS. 19D,20A, 22A, 22C, 23B, and 23D, may be secured to a strip's underside as isa support 710 (FIG. 19B) and the strips in these figures and thesupports may be made of any of the materials listed above regarding thestrips 707, 708 and supports 710.

FIGS. 22A and 22B show a hump 725 of a strip 726 with an internalsupport 727 adhesively secured to the strip 726 with epoxy.Alternatively, the support 727 may be welded to the strip 726.Preferably when viewed as in FIG. 22B the support 727 occupies less than10% of the area beneath the hump 725 and most preferably less than 5%.As with any other internal support and hump disclosed herein, the hump725 and/or support 727 may have one or a series of fluid flow holestherethrough, as shown with the holes 728, 729 in FIG. 22C.

FIGS. 23A–23C illustrate changes to a screen assembly 730 disclosed inU.S. Pat. No. 5,720,881 which is incorporated fully herein. The screenassembly 730 has a plate 731 with holes 738 therethrough and amulti-layer screen 732 epoxied together and bonded to the plate 731.

As shown in FIG. 23B, support 733 underlies a ridge 734 of the screen732 and support 735 with a series of fluid flow holes 736 therethroughunderlies a ridge 737.

It is within the scope of this invention to use one or more supports 733and/or 735 (and/or one or more of any of the supports disclosed herein)under one, two, three, more than three, or all of the ridges of thescreen 732 (or of any screen or screen assembly disclosed in U.S. Pat.No. 5,720,881). In one aspect each ridge may have a series of spacedapart supports and, in another aspect, supports under one ridge areoffset from those under another ridge.

Although it is not preferred, in certain embodiments the support(s) maybe loose under the ridges. As shown in FIG. 23B the support 733 issecured to the screen 732 and to the plate 731 and the support 735 issecured to the screen 732.

As shown in FIG. 23C the width of a support may be such that, as viewedfrom above, it does not block off the openings 738 (support 733) or,alternatively it does block off openings 738 (support 736).

FIG. 23D shows a screen 740 like the screen assembly 730's screen 732,but with no lower plate 731. It is to be understood that the screens 732and 740 represent any known single or multi-layer screen or screenassembly with screen(s) bonded together or unbonded. It is within thescope of this invention to use one or more supports (any disclosedherein) with each of the various screen assemblies disclosed in U.S.Pat. No. 5,720,881 including but not limited to those of this patent'sFIGS. 2, 4, 8 and 9.

Ridges 741, 742, 743 of the screen 740 each has an internal support 744,745, 746, respectively secured thereto and thereunder. It is within thescope of this invention for the screen 740 to have only supports 744,745, or 746, to have them under each ridge, for such supports to extendalong and under the entire length of a ridge, or for there to be aplurality of spaced apart supports beneath each ridge. The support 746is shown with a series of fluid flow holes 747 therethrough, but it maybe solid and either or both of the supports 744, 745 may have a seriesof fluid flow holes therethrough.

FIG. 24A shows a screen 800 according to the present invention with mesh802 supported on spaced-apart straps 806. The mesh 802 may be anysuitable known mesh, screen, meshes, screens, or combination thereof,secured together or lying on each other and/or partially bonded orsintered together, or so connected to each other over substantially allof their area. In the screen 800, the mesh 802 is, in one aspect, a wiremesh that is bonded to the straps 806.

The straps 806 are secured to hookstrips 804, e.g. as previouslydescribed for straps herein.

As shown, the screen 800 has three spaced-apart ramps 808, 810, 812. Adewatering area or pool 822 is defined between the two ramps 808, 810and a dewatering area or pool 820 is defined between the two ramps 810,812. Side flow paths 824, 826 are positioned between ends of the ramps808, 810, 812 and the hookstrips 804.

In one aspect the ramp 808 is located so that fluid material isintroduced onto the screen 800 in an area behind (to the left in FIG.24C) the ramp 808 and which includes one of the straps 806 therebeneathto counter effects of the impact of the fluid material on the wire mesh802 in this area. Also such a location of the ramp 808 with respect tothe strap 806 facilitates dewatering of solids in this area whileinhibiting screen wear. Liquid rising to the top can exit through thescreen ramp. Similarly a strap 806 traverses the areas 822 and 826.

Alternatively, the ramp portions and straps may be positioned so thatany or part of the ramp portions overlie a strap or a portion of astrap. The ramp portions may be spaced apart any desired distance. Inone aspect the screen 800 is about 36 inches by 45½ inches; theright-hand edge (as viewed in FIG. 24C) of the ramp 808 is between aboutthree to about five inches or more from the left-hand edge of the ramp810; the right-hand edge of the ramp 810 is between about three to aboutfive inches or more from the left-hand edge of the ramp 812; theright-hand edge of the ramp 812 is between about three to about fiveinches or more from the right edge of the screen 800; and the ramps arebetween about three to about five inches wide (horizontal dimension asviewed in FIG. 24E) and about ½ inch high (as in FIG. 24E). Each ramp808, 810, 812 has a ramped surface 808 a, 810 a, 812 a, respectively atan angle, preferably, between about twenty to about forty degrees fromthe horizontal, more preferably between about twenty-five to aboutthirty degrees, and in one particular aspect about twenty seven-degrees.Each ramp also has a rear face at between about eighty to about onehundred twenty-five degrees to the horizontal, more preferably betweenninety and one hundred twenty degrees, and in one particular aspectabout one hundred fifteen degrees.

FIGS. 25A–25E show cross-section views for a variety of ramp profiles840–848 according to the present invention. In certain preferredembodiments ramp heights range between ¼ inch and 1½ inches and rampwidths range between about one inch and about five inches.

It is within the scope of this invention to provide a screen with one,two, three, four, five, six or more ramps and the ramps may be the sameor different on a multi-ramp screen—and may be any ramp with any profiledisclosed herein. FIG. 26 shows a screen 850 like the screen 800 (andlike numerals indicate the same parts), but with an additional series oframps 808 a, 810 a, 812 a.

FIG. 27 shows a screen 860 like the screen 800 (and like numeralsindicate the same parts), but with only one ramp 812.

FIG. 28 shows a screen 870 like the screen 800 (and like numeralsindicate the same parts), but with divided ramps 811, 813, 815 (eachwith ramp portions 811 a, 811 b; 813 a, 813 b; 815 a, 815 b,respectively) each having a flow path 821, 823, 825 between rampportions. It is within the scope of this invention to provide: a fullundivided ramp for any of the ramps 811, 813 or 815; a flow path betweenramp portions of any desired width, including, but not limited to,between about three inches and about five inches; and to provideadditional flow paths (one, two, or more) through the ramp portionsthemselves. In one aspect, ramp portions are offset to provide a moretortuous path for wet solids. Any one or two of the paths 821, 823, 825may be deleted by providing an undivided ramp across the screen 870.

In any screen disclosed herein with one, two or three ramps on one sideof the screen (as viewed from above), e.g. as in FIGS. 24D, 27 and 28,it is within the scope of this invention to provide one, two or moreramps on the other side of the screen.

Different ramp profiles may be used on the same screen. FIG. 29A showspart of a screen 874 according to the present invention (like the screen800) with mesh 875 and spaced-apart ramps 877, 878. Straps 876 (like thestraps 806) are beneath the mesh 875. FIG. 29B shows a differentlocation for the straps 876.

FIG. 30A shows a screen 880 according to the present invention (like thescreen 800) with mesh 885 in straps 886 (like the straps 806) and ramps887, 888. FIG. 30B shows the screen 880 with additional straps 886. Thescreens of FIGS. 29A–30B may have hookstrips and straps like the screens800, 850, 860 and/or 870.

Although a series of spaced-apart parallel straps is not the legalequivalent of a perforated plate, a screen as described herein (FIGS.24D–30B) and/or any ramp or ramp portion as described herein may be usedon a perforated plate and, in particular aspects, on a perforated plateof any prior art screen instead of the prior art mesh(es) and/orscreen(s) used thereon, including, but not limited to, with flat and/orthree-dimensional screens and/or with the plates of the screens ofprevious U.S. Pat. Nos. 4,575,421; 5,720,881; 5,417,858; 5,783,077;5,417,859; 5,417,793; 5,636,749; 4,033,865; 5,221,008; 4,819,809;4,065,382; 3,929,642; and 5,211,291. Such a screen is illustrated by thescreen 890 of FIG. 31 which has mesh 892; ramps 893, 894, 895; and aperforated plate 896 (side view shown without showing perforations thatdo extend through the plate). It is also within the scope of thisinvention to use a perforated plate under a portion of the screen meshand one or more straps under the remaining portions of the screen mesh,with one or more ramped screen portions over the perforated plate and/orover the strap(s).

FIGS. 32A and 32B show a screen 900 like the screen 860 (like numeralsindicate the same parts) but with an additional ramp 812 c at the sideof the screen opposite the side with the ramp 812 d. Such a ramp 812 cmay be used with the screens 800 or 870. Flow paths may be used throughthe ramp 812 c and/or through the ramp 812 d. The ramps 812 c and 812 dare separate pieces that are bonded to, sintered to, and/or secured tothe mesh 802 and/or to a strap 806, e.g. by any structure or securementapparatus or method disclosed herein (e.g., but not limited to as inFIGS. 1A, 3D, 9–17E). Any ramp or ramp portion herein may also be soconnected to a mesh, screen, plate, and/or strap and/or secured to themesh (screen, strap, and/or plate), e.g. by any structure or securement.

Referring now to FIG. 33, a vibratory separator system 910 according tothe present invention has a screen 920 (with screen or screening clothor mesh as desired) according to the present invention mounted onvibratable screen mounting apparatus or “basket” 912. The screen 920 maybe any screen disclosed herein or have any combination of any feature orfeatures of any screen or screen part disclosed herein; and any suchscreen may be used with any appropriate shaker or screening apparatus.The basket 912 is mounted on springs 914 (only two shown; two as shownare on the opposite side) which are supported from a frame 916. Thebasket 912 is vibrated by a motor 922 and interconnected vibratingapparatus 918 which is mounted on the basket 912 for vibrating thebasket and the screens. Elevator apparatus 928 provides for raising andlowering of the basket end. The screen 920 may be any screen disclosedherein, including, but not limited, those of FIGS. 24D–32A and those inthe Figures beyond FIG. 33. As shown the screen 920 is like the screen800 of FIG. 24D. In certain aspects using a ramped screen as in FIG. 24Aproduces processed cuttings with an oil content of 3% or less and awater content of 20% or less when the screen is used in a multi-screenBRANDT LCM2D shaker beneath two standard DX 210 screens; and in aparticular embodiment of such a screen, the oil content is less than 2%with a water content less than 15%. Any ramp disclosed herein may have acurved or undulating shape as viewed from above instead of the straightshape, e.g. as disclosed in FIG. 26. One or more ramps and/or dividedramps as described above may be used on any screen disclosed hereinhaving one or more screens formed with an undulating shape.

FIG. 35A shows a screen 1010 according to the present invention with alower base, support or frame 1012, three undulating mesh screens 1014 onand/or bonded to the frame 1012, and an upper mesh or screen 1016. Thescreens 1014 may themselves be bonded together, e.g. with epoxy,welding, and/or sintering. Rubber strips, plastic strips tape, cushionor cushions 1018 are positioned between the screen 1014 and the upperscreen 1016. The strip(s) or cushion(s) are optional. As shown thestrip(s), tape(s), or cushion(s) 1018 are secured to the screen 14 (orto crests thereof), but it is within the scope of this invention tosecure them (or some of them) to the screen 1016. To effect suchsecurement any suitable glue, epoxy, weld, and/or sintering may beemployed. The frame 1012 may be any suitable known base, frame orsupport.

It is within the scope of this invention for the screen 1014 to be anyknown screen, mesh, screens, meshes, or combination thereof, bondedtogether, unbonded, or bonded at only certain locations and with anyknown shape as viewed either from above or on end (as in FIG. 35A). Itis within the scope of this invention for the upper screen 1016 to beany known screen, mesh, screens, meshes, or combination thereof, bondedtogether or unbonded, and with any known shape. As shown in FIG. 35B,the screen 1014 is three mesh screens bonded together with coarser meshon the bottom, medium mesh in the middle, and finer mesh on top. Thescreen 1016 as shown may be a scalping screen of a mesh coarser than thefinest mesh of the screen 1014 or of a multi-layer coarser mesh. Inanother aspect the screen 1014 is a single screen of closely woven meshmade of any suitable material, e.g. stainless steel and/or plasticmaterial and the screen 1016 is a single screen of coarser mesh made ofany suitable material (e.g. but not limited to stainless steel and/orplastic), with the screen 1014 on a metal or plastic frame or support.Alternatively or additionally, instead of the frame 1012 any knownperforated plate, strip, or series of straps or strips may be used. Aseries of strips is not legally equivalent to a perforated plate.

In one aspect the strips 1018 are fused plastic strips aligned withpeaks of the undulating fine mesh. Such strips may be made of rubber(e.g. nitrile) or plastic, e.g. polypropylene, to inhibit or preventabrasion of the finer meshes. Such strips can be glued to the bottom ofthe screen 1016 and/or the screen 1014. Also the screen 1016 can beglued to the screen 1014.

End plugs 1013 and 1015 (FIG. 35D) sealingly close off open ends of thescreen 1010. These end plugs may be made of rubber, metal, wood,plastic, Teflon™ material, or urethane. The plugs 1013 extend along twosides of the screen along crests of the screening material to completelyseal the sides. The plugs are held in place by friction fit, glue,epoxy, welding and/or sintering. Alternatively, the ends may be coveredwith screen material.

Fluid flow on the screen 1010 from either end may be from top-to-bottomas viewed in FIG. 35A, bottom-to-top, or from one side to the other.

In one aspect the screen 1016 is a scalping screen of woven steel mesh.In another aspect, it is woven plastic or synthetic or composite mesh;and in another aspect it is a combination of woven steel and wovenplastic or synthetic or composite mesh. The screen 1016 may be the samemesh or coarser mesh than that of the screen 1014 or of any layerthereof.

In this embodiment the areas 1017 between the screen 1016 and the screen1014 are open. The screen 1016 protects the mesh of the screen 1014 fromabrasive particles. When the screen 1016 is of a coarser mesh than thatof the screen 1014, relatively larger particles retained on the screen1016 are prevented from damaging and/or hindering flow through thescreen 1014.

With the screen 1010 as shown liquid flow through the screen isincreased by reducing the thickness of the solids bed of the finer meshscreens by the separation of larger particles with the screen 1016.

Use of the upper screen 1016 increases stability and rigidity of thescreen 1010, improving solids conveyance across and off, rather thanthrough the screen 1016 thereby facilitating liquid flow through thescreen. Solids that do not flow through the screen 1016 do not encounterthe lower finer mesh screens and do not reduce flow through the finermesh screens. Use of the upper screen 1016 also reduces the initialimpact load of flow onto the screen 1014 at a feed entrance to thescreen, thereby extending screen life.

FIG. 36 shows an alternative embodiment of the screen 1010 withidentical parts (indicated by the same numerals) but with additional endplugs 1019 between the upper screen 1016 and the screen 1014. Such“double plugging” may be used on either or both screen ends. A fluidand/or particles introduced to the screen 1010 first encounters thescreen 1016 and then material flowing through the screen 1016 flows tothe screen 1014. The plugs 1019 may be made of the materials describedfor the plugs 1013, 1015 and the plugs 1019 may be similarly installedand/or secured in place. Any of the plugs 1013, 1015, 1019 may bedeleted in certain embodiments.

FIG. 37 shows a screen 1020 like the screen 1010, but without thecushion members 1018. A scalping screen 1026 is secured at points 1027to a screen 1024 on a base, frame, or support 1022. The screens 1024,1026 may be in any of the forms discussed above for the screens 1014,1016, respectively and the base, frame, or support 1022 may have any ofthe forms or alternatives discussed above for the base, frame, orsupport 1012. The screen 1026 may be secured to the screen 1024 in anysuitable way, including but not limited to with glue, epoxy, fusedplastic and/or by welding and/or sintering.

FIG. 38A shows a screen 1030 with a base, frame, or support 1032 onwhich is a screen 1034 to which is secured a corrugated upper screen1036 with optional items 1038 (like the tape, cushion, strips 1018,above). In one aspect the screens 1034 and 1036 are of different mesh;in one aspect with coarser mesh in the screen 1036; and in anotheraspect the two screens are of a similar mesh. The screens 1034, 1036 maybe like the screens 1014, 1016 and 1024, 1026 respectively with respectto mesh size and materials. The base, frame, or support 1032 may be likethe items 1012, 1022 and their alternatives described above. As shownthe screen 1034 includes a fine mesh screen 1034 a on top of a coarsermesh screen 1034 b. A third screen (not shown) of medium mesh (e.g. asin FIG. 35B) may be used. If used, the upper screen 1036 may be securedto or simply rest on the items 1038 and the lower screen 1034 may besecured to or simply rest beneath the items 1038. It is to be understoodthat the items 1038 represent any of the strip(s), tape, etc. describedabove regarding the items 1018.

End plugs 1035 (FIGS. 38C, 38D) sealingly shut off the end openingsbeneath corrugations of the screen 1034. Open areas 1037 extend betweenthe screens 1034, 1036. Fluid flow on the screen 1030 may betop-to-bottom as viewed in FIG. 38A, bottom-to-top, or from one side toanother.

FIG. 38E shows an alternative embodiment of the screen 1030 with plugs1039 sealingly closing off the ends of the areas 1037 to fluid flow. Theplugs 1035, 1039 may be like, and installed as, any of the plugsdescribed above.

The screens in FIGS. 35A–38E have the advantages of an upper screen asdescribed for the screen 1010.

FIG. 34B shows a system 1000 according to the present invention withparts like those of the system of FIG. 34A; but with a shale shaker Khaving a screen or screens S according to the present invention (anyscreen or screens disclosed herein). The screen(s) S are mounted in atypical shaker basket B and one or more vibrators V (any known suitableshaker vibrator) vibrate the basket B and hence the screen(s) S.

FIG. 39A shows a screen assembly 1100 according to the present inventionwhich has a tubular frame 1102 with interconnected outer frame members1103, 1104, 1105, 1106 and crossbars 1107, 1108 each with twospaced-apart ends connected to an outer frame member.

Screening material 1109 is located over the crossbars and attached tothe outer frame members (and, in certain aspects to the crossbars) byany suitable known method, connectors, glue, welding, etc. The screeningmaterial 1109 may be any known screen and/or mesh; in any combination ofone, two, three or more layers; connected, fused, glued, and/or sinteredtogether in any known way either substantially over the entire surfaceof screening material or only in portions thereof.

Connected on top of the screening material 1109 are a plurality ofspaced-apart ramps 1110 each with a base 1112 and a portion 1114projecting up from the screening material 1109. AS shown there is anobtuse angle a between each ramp's base 1112 and projecting portion1114. The angle a may be any desired angle from zero to one hundredeighty degrees (i.e., acute, right, obtuse or straight angle). Incertain aspects the base portion of one, some or all of the ramps may bedeleted, and the projecting portions alone are connected to thescreening material. The ramps (and any other screen component disclosedherein for connection to a screen assembly) (the bases and/or theprojecting portions) may be connected to the screening material with anysuitable connector or method, including, but not limited to, withscrews, rivets, welding, gluing, releasable cooperating hook-loopfastener material, solder, adhesive, tape (single or double-sided),and/or sintering.

As shown in FIG. 39A a line 1111 defining a boundary between each rampbase and projecting portion is located above a crossbar 1107 andportions of each base are over parts of the crossbars 1108. It is withinthe scope of this invention for these ramp base portions to also beconnected to these cross bar portions as well as to the screeningmaterial; alternatively, there is no such connection, connection only tothe crossbars 1107, or connection only to the crossbars 1108 (as can bethe case for any screen assembly according to the present invention).

FIG. 39B shows another version of the screen assembly 1100 designated1100 a with like numerals indicating like parts. In the screen assembly1100 a, the ramp bases 1112 are positioned above the crossbars 1107 withthe lines 1111 located between crossbars, i.e., not over a crossbar.Alternatively, it is within the scope of this invention to place one orsome of the ramps as in FIG. 39A and one or some of the ramps as in FIG.39B. Also as shown the ramps are generally parallel to the crossbars1107 and the outer frame members 1104, 1106; but it is within the scopeof this invention for the ramps to be at an angle to these items and, inone aspect for different ramps to be at different angles, e.g., but notlimited to, a plurality of spaced-apart ramps with every other ramp atone angle and the ramps between them at a different angle—which in oneaspect includes ramps with an acute angle between adjacent ramp ends.

FIG. 40 shows a screen assembly 1120 according to the present inventionwhich has two spaced-apart hook strips 1122 between which and to whichare connected a plurality of spaced-apart support strips 1124 (which maybe as in disclosed herein or as any disclosed in any parent applicationor patent listed herein) on which is mounted screening material 1129(like the screening material (1109 or as any disclosed herein) and mayinclude a diamond-patterned layer 1128 (e.g. of metal, glue, plastic,adhesive, rubber, or epoxy). A plurality of ramps 1123, like the ramps1110 above, are connected to the screening material 1129. A line 1125defining a boundary between a base 1121 and a projecting portion 1127 ofeach ramp is located above a strip 1124; but it is within the scope ofthis invention, as with the screen assembly of FIG. 39A, to locate thisline as desired. The hook strips 1122 may be of any known shape and/orconfiguration for hooking apparatus for shale shakers and vibratoryseparators (including but not limited to any known side channels, hooks,or strips for mounting a screen to a shale shaker).

FIG. 41A discloses a plurality (1131–1135) of various ramps according tothe present invention useful with any screen assembly according to thepresent invention and which may be used instead of any ramp shown on anyscreen assembly herein; alternatively, a combination of any of theseramps on a single screen assembly may be used according to the presentinvention.

FIG. 41B shows end views of the ramps of FIG. 41A. Certain of the rampsaccording to the present invention have an enclosed area and, therefore,an end which, according to the present invention, may be open or closed(e.g. as in ramps 1131, 1133, 1134, 1134). It is within the scope ofthis invention to leave these ramp ends open; partially open (e.g. top,bottom, one side or the other side closed off); or closed off eitherwith solid material or with screen or mesh (as shown in the ramps 1131and 1133 closed off, respectively with screening material 1136, 1138).Screening material used to close off or partially close off a ramp endmay be any screening material disclosed herein and the ramp ends thusclosed-off may be flat (i.e. perpendicular to the surface of the screenassembly) or non-flat, e.g. as disclosed in U.S. application Ser. No.09/634,610 filed Aug. 5, 2000, incorporated fully herein for allpurposes. The ramps 1131, 1133, 1134, 1135 each has a base 1141, 1143,1144, 1145, respectively, with portions on either side of a projectingramp portion 1151, 1153, 1154, 1155, respectively. Suitable connectionof these base portions on either or both sides of the projectingportions may be made to screening material of a screen assemblyaccording to the present invention. It is also within the scope of thepresent invention to fold either or both base portions either under orover prior to attaching the ramps to a screen assembly.

FIG. 42A shows a screen assembly 1160 according to the present inventionthat has an outer frame with interconnected frame members 1161, 1162,1163, 1164 (however it is within the scope of this invention for theramps of the screen 1160 to be used on a screen like that in FIG. 40that has hookstrip sides). Ramps 1171–1175 are connected to screeningmaterial 1169.

In one aspect the ramps 1171–1175 are made of mesh or screen or acombination thereof that can be folded down or pushed down and remainsin the “down” position, i.e., it has memory. As indicated any desiredpart of a ramp may be positioned lower than the other parts.

Ramp 1171 has a base 1171 a, a projecting portion 1171 b, and a portion1171 c that has been pushed down. FIG. 42A shows an end view of the ramp1171 and FIG. 42B shows a cross-section view of the lower portion 1171C.Ramp 1172 has lower, pushed down portions 1172 c; ramp 1173 has lower,pushed down portions 1173 c and 1173 d; ramp 1174 has lower pushed downportions 1174 c; and ramp 1175 has lower pushed down portions 1175 c.Alternatively, the ramps 1171–1175 are preformed of suitable materialwhich has no memory (does not retain a shape, position, or configurationinto which it is pressed, pushed, or moved), e.g. metal, rubber, orsolid plastic (with or without fluid-passing perforations across itssurface). All of the ramps of a particular screen assembly according tothe present invention may be like any one of the ramps 1171–1175; or anycombination of such ramps may be used according to the presentinvention. It is also within the scope of this invention to makedifferent parts of a ramp out of different screening material. Forexample, in the ramp 1171 the base 1171 a and part 1171 b may be madefrom screening material of a mesh size similar to that of the screeningmaterial 1169 and the portion 1171 c may be made of a much finer meshthat lays down (rather than a mesh with memory that needs to be pushedor folded down). Upper or projecting portions of the ramps (e.g.portions 1171 b, 1127, 1114) may be made of non-memory material that isso non-rigid that it moves up and down or flaps uncontrollably as thescreen assembly is vibrated (e.g. a shale shaker processing fluid withdrilling mud and drill cuttings or other solids entrained therein). Anyprojecting portion or upper portion of a screen or ramp disclosed hereinmay be made of multiple layers, e.g. a non-memory movable layer with aone, two, or more lower and/or upper layer(s) of metal or of syntheticmaterial, perforated or not, to inhibit or prevent up/down oruncontrollable flapping and/or to inhibit or prevent wear of and damageto such a non-memory layer. Optionally, different parts of a singleprojecting portion may have one or more of these reinforced areas alongthe length of the projecting portion. In one aspect a coarse mesh isused beneath a projecting portion and a fine mesh is used on top so thatfine solids or particles separated from a fluid more easily climb up theprojecting portion. Alternatively, a reinforcing material (mesh, screen,solid) may be used around the top, bottom, and/or side edges of aprojecting portion to strengthen the projecting portion. Also, anupstanding ramp portion or a front ramp portion may be made of a verycoarse mesh, e.g. 19 mesh, for strength and stability.

FIGS. 42D and 42E illustrate other possible ramp end profiles for ramps1176, 1177 and relative sizes for base and projecting portions which maybe used for any ramp herein. Also any number (e.g. one, two, three,four, five, six, or more) of any ramp 1171–1175 may be used on anyscreen.

FIG. 43 shows a screen assembly 1180 according to the present inventionwhich has an outer frame 1182 (like the frame of the screen 1160) withcrossbars and screening material 1189 like that of the screen 1160.Ramps 1181–1185 represent any ramp according to the present invention.As shown, the ramps are offset from each other, as may be any two rampsof any screen assembly according to the present invention and any number(e.g. one, two, three, four, five, six, or more) of any ramp may beused. Also any portion of any ramp may be deleted providing a flow paththrough that ramp at that area. In one particular embodiment centralportions e.g. between one and fourteen inches wide, are deleted fromalternating ramps, beginning with ramp 1181 or with ramp 1182.

FIG. 44A shows a piece of screening material 1190 which may be anyscreening material or combination thereof disclosed herein. As shown inFIG. 44B, the screening material 1190 has been formed or folded to formupwardly-projecting portions 1191 and 1192 that can serve as ramps forany screen assembly according to the present invention with one or moresuch ramps. As shown the lower ends of the upwardly projecting portionsare open; but it is within the scope of the present invention to closeoff these ends (or the ends of any ramp disclosed herein) with solidsmaterial or with material such as screen or mesh that permits fluid flowtherethrough.

FIG. 45A shows a piece of screening material 1200 which may be anyscreening material disclosed herein. As shown in FIG. 45B the screeningmaterial 1200 has been formed or folded to make a ramp 1201 with aninclined portion 1202 and a wall portion 1203. The area under the rampmay be open or closed off (with solids or with fluid-passing material).

FIG. 46A shows a piece of screening material 1210 which may be anyscreening material disclosed herein. As shown in FIG. 46B the screeningmaterial 1210 has been formed or folded to make a ramp 1211 with aninclined portion 1212 and a front portion 1213. The open area under theinclined portion may be open or closed off (with solids or withfluid-passing material). The front portion 1213 is shown as contactingthe screening material 1210. It is within the scope of this invention toalso connect the front portion 1213 to the screening material 1210either all along the length of a ramp with such a profile or atspaced-apart points along the length.

FIG. 47A shows a piece of screening material 1220 which may be anyscreening material disclosed herein. As shown in FIG. 47B the screeningmaterial 1220 has been formed or folded to make a ramp 1221 with aninclined portion 1222 and a front portion 1223. The open area (1223 a)under the inclined portion may be open or closed off (with solids orwith fluid-passing material). The front portion 1223 is shown ascontacting the screening material 1220. It is within the scope of thisinvention to also connect the front portion 1223 to the screeningmaterial 1220 either all along the length of a ramp with such a profileor at spaced-apart points along the length. FIG. 47C shows another ramp1224 made (formed or folded) with the screening material 1220. The ramp1224 has an inclined portion 1225, a front portion 1226 and a lowerportion 1227. The front portion 1226 may be connected to the screeningmaterial at points or all along its length, as may be the lower portion1227. Also the end of the lower portion 1227 may touch or be connectedto the inclined portion 1225. Alternatively, the portion 1227 may extendout in front of the ramp rather than beneath the portion 1224.

FIG. 48A shows an end profile of a ramp 1230 according to the presentinvention, e.g. like the ramp 1135 above, FIG. 41A. FIG. 48B shows theramp 1230 in place connected to screening material 1231 which has anupwardly projecting portion 1232 (formed or folded into the screeningmaterial). The ramp 1230 may be connected to the portion 1232. Any rampaccording to the present invention with a raised portion may beso-positioned above any screening material disclosed herein with anupwardly-projecting portion.

FIG. 49 shows a ramp 1240 (end view or cross-section) according to thepresent invention (like the ramp 1230) connected to screening material(any disclosed herein or any combination thereof) 1241 with welds,connectors or glue 1243 (any one of which or all but one may bedeleted). An upwardly-projecting portion 1242 of the screening material1241 has been formed or folded to correspond in shape to the projectingportion of the ramp 1240. For any shape ramp according to the presentinvention screening material can be formed or shaped to correspond inshape to a ramp shape for positioning of and/or connection of a ramp toscreening material. Any ramp described herein as made or formed ofscreening material may be made or formed of one, two, three or morelayers of screening material and/or mesh.

FIG. 50A shows a screen 1250 according to the present invention withscreening material 1251 (any disclosed herein or any combinationthereof) with spaced-apart ramps 1252 connected to the screeningmaterial (which may be any ramp herein including, but not limited to,any ramp herein that is a separate piece connected to screening materialor any ramp folded from screening material). A mass of solids 1253 (e.g.solids separated from drilling mud flowing across the screen 1250 in ashale shaker) is moving over the screen 1250. As shown in FIG. 50B, theramps 1252 are configured, sized, and made of such material that themass of solids 1253 moves the ramps downwardly as it passes over them,facilitating movement of the mass of solids across the screen. As shownin FIG. 50C the ramp that was moved down by the mass of solids has movedor sprung back to its initial position. In certain prior art machines, arelatively large mass or conglomeration of separated solids might not beable to climb or be moved over an upwardly projecting portion or ramp ofa screen.

FIG. 51A shows a screen 1260 according to the present invention whichhas a frame 1261 made of frame members 1262, 1263, 1264, 1265 with aplurality of cross members 1266. Between pairs of frame members andcross members, and between pairs of cross members are connected pieces1267 of screening material (any disclosed herein or any combinationthereof). Alternatively, a single piece of screening material may beplaced over the frame 1261 and folded to result in screen part placementas in FIG. 51B.

FIGS. 52, 53 and 54 illustrate various types of frame and cross membersuseful in screens as in FIG. 51A. FIG. 52 shows a screen 1270 with crossmembers 1271 and frame members 1273 having a “C” channel shape whenviewed in cross-section; and an end 1244 of a piece of screeningmaterial 1275 is in and connected to each channel.

FIG. 53 shows a channel member 1280 which may be used for a frame orcross member, e.g., but not limited to, in the screens 1260 and 1270.The channel member 1280 has a lower portion 1281 on which an end 1282 ofscreening material 1283 is placed and to which it is connected. Such achannel may be used for a screen as in FIG. 51A. FIG. 54 shows a channelmember 1273 a, like the channel member 1273, but with holes 1273 btherethrough.

FIGS. 55A and 55B show alternative frame and cross member profiles 1295a, 1295 b, 1295 c, 1295 d and 1296 a, 1296 b, 1296 c, 1296 d, 1296 e,respectively (cross-section) for any of the frame or cross membersdisclosed above (with or without holes in any or all of the parts of theprofiles).

FIG. 55C illustrates that any cross member in any frame according to thepresent invention may have perforations along its length to facilitatesolids separation. As shown in cross-section, channel members 1290 a,1290 b, 1290 c and 1290 d (shown in cross-section) have holes htherethrough along their lengths. Any series of holes may be deletedfrom any channel member.

FIG. 56 shows a screen assembly 3000 with some parts like those of priorart U.S. Pat. No. 4,575,421; however as described below, various partsof the screen assembly 3000 are held together by sewing material (e.g.thread, wire, string, filaments, cord, twine, yard or fiber). U.S. Pat.No. 4,575,421 is incorporated here fully for all purposes, including,but not limited to the parts of the screen assembly 3000 which are likethe parts of the screen assemblies in the patent. Sides 3008 may be anyknown channel-shaped member, hookstrip, or frame sides. Alternatively arigid frame with four sides may be used.

A plurality of layers of screening material 3002, 3003, and 3004 arepositioned above a plate 3001 (like the plates, including but notlimited to the plate 11, in U.S. Pat. No. 4,575,421). The layers 3002,3003 and 3004 are like the layers, respectively, 24, 25, 26 as describedin U.S. Pat. No. 4,575,421. It is, however, within the scope of thisinvention to delete any one or two of the layers and for any of thelayers 3002, 3003, 3004 to be any screening material or mesh disclosedherein or combination thereof; and it is within the scope of thisinvention for the plate 3001 to be any support plate structure screen,frame, or series of strips (although these things are not legalequivalents) known in the art.

The layers 3002, 3003, 3004 are sewn together by sewing material.Exemplary lines of sewing material 3014 and 3016 are shown in FIGS. 56,57, and 58. It is to be understood that such lines of sewing materialsewing the layers together may extend in spaced-apart fashion oversubstantially all of the surface of the layers with any desired spacingbetween lines of sewing material. It is also within the scope of thisinvention for the sewing material to be in lines that are generallyparallel to the sides of the screening layers, as shown; for the sewingmaterial lines to extend diagonally across the screening material; forthe sewing material lines to be at an angle other than diagonal acrossthe screening material; and/or for lines of sewing material tointersect, forming any desired pattern including, but not limited to, apattern corresponding to shapes formed by members of a lower supportingmesh, structure or plate. Such lines of sewing material may also be usedto join together either layers 3002 and 3003, 3002 and 3004, and/orlayers 3003 and 3004.

Lines of sewing material 3010 and 3012 sew together the plate 3001 andthe layers 3002, 3003 and 3004. The lines 3010 and 3012 may take any ofthe forms and positions described above for the lines 3014, 3016. In oneaspect “edge stitching” may be used to sew screening material to theplate. It is also within the scope of this invention to sew one, two,three or more layers of screening material to a frame that supports thescreening material.

The sewing material used to sew together any two or more layers ofscreening material and/or mesh, or any support structure or plate andone or more layers of screening material may be any suitable knownsewing material, including, but not limited to, thread, wire, yarn,string, twine, cord, and filament line (any of which may be mono- ormulti-strand or filament with different or similar strands or filamentsin multi-component sewing material). Such sewing material may be made,e.g., of natural, plastic, or synthetic thread, yarn, cord or wirematerials; composite materials; polymer(s); elastomer(s); rubber;phenolic resin(s); metal (including but not limited to steel, stainlesssteel, bronze, brass, copper, zinc, aluminum and any combination oralloys of them); KEVLAR™ material; and polytetrafluoroethylene orTeflon™ material—any of which may be coated with plastic, metal,polymer, elastomer, or resin. Sewing material of any cross-sectionalsurface area and/or cross-sectional shape (or of any suitable diameter)may be used. Different sewing materials may be used for differentstitches and/or lines of stitches on a single screen or screen assembly.The needle(s) used may be any suitable known needle and may be made ofany suitable metal, plastic, composite, and/or fiberglass material. Inone particular aspect KEVLAR™ thread with a diameter of 0.009 inches isused. In one particular screen using such KEVLAR™ thread there are threelayers of screening material sewn together.

The sewing together of any two or more items may be done according tothe present invention by hand, with a manually operated sewing device ormachine, or with any automatic sewing machine. Any known sewing stitchor pattern may be used. In certain aspects a sewing needle is used whichis sized so that damage to the layers and/or support is minimized oreliminated. In one such aspect, a needle is selected of such size thatit penetrates between and moves between adjacent wires or screencomponents rather than making a dent, gouge, gash, tear or recess in awire (or screen component) of a screen and rather than breaking orweakening a wire of a screen.

Any stitch or line of sewing material may, optionally, be deleted fromthe screen assembly 3000 (or from any sewn screen assembly disclosedherein). It is within the scope of this invention to delete all lines3012, 3014 and all lines sewing together the layers of screeningmaterial 3002, 3003, 3004 and to rely on the lines 3010, 3012 and othersspaced-apart from them that sew together all of the layers of screeningmaterial and the plate 3001. Alternatively between lines like the line3010, lines like the line 3014 may be used to hold the layers 3002–3004together (and likewise for lines like 3012 and 3016).

U.S. Pat. No. 4,575,421 refers to an adhesive or bonding that securesparts together. The screen 3000 may be made with no such adhesive orbonding. Alternatively, such adhesive (e.g., but not limited to, glue orepoxy) or bonding may be used in addition to any sewing materialdescribed above; or a combination of one or more spaced-apart lines ofsewing material and adhesive between and/or on or beneath such lines maybe used. In one aspect the layers 3002–3004 may be adhesively securedtogether and lines like the lines 3010 and/or 3012 used to sew thelayers to the plate 3001, or the layers 3002–3004 are sewn together andthen adhesively secured to the plate 3001. Any two or more metal layersand/or plate may be sintered together over a portion or oversubstantially all of this area. One or more separate, individualstitches or knots of sewing material may be used instead of a line of acontinuous thread, etc. for any line of sewing material describedherein.

FIGS. 70A and 70B show screen assembly 3108 according to the presentinvention with a perforated plate 3110 (which may be any plate referredto herein and any plate used in the prior art) which has a plurality ofapertures, holes or openings 3112 therethrough. A wire mesh layer 3114is secured to the plate 3110 with thread stitches (or knots) 3115. Thelayer 3114 may be any known suitable mesh or screen, meshes or screens,with one, two, three, or more layers.

FIGS. 71A and 71B show a screen assembly 3120 according to the presentinvention with a perforated plate 3121 (like the plate 3110, FIG. 70A)with apertures, etc. 3122 therethrough. Wire or screening mesh layers3124 are sewn together with thread stitches (or knots) 3126. The layers3124 are sewn to the plate 3121 with thread stitches (or knots) 3125.Suitable staples may be used for any stitch in the screen assemblies3108 and 3120.

The plates and screen assemblies of FIGS. 70A and 71A are shownpartially; but it is to be understood that the apertures, mesh,stitching and plates are on their entire breadth and surfaces as shownpartially.

FIGS. 59 and 60 show a screen assembly 3020 according to the presentinvention which has parts like those of U.S. Pat. No. 5,417,858(incorporated fully herein for all purposes, including, but not limitedto the parts of the screen assembly 3020 which are like parts of thescreen assemblies in the patent). However, as described below, variousparts of the screen assembly 3020 are held together by sewing material.

The screen assembly 3020 has a plate 3021 (like the plate 3001 describedabove) on which are positioned a coarse support screen 3022 and a finescreening screen 3023. The screens 3022, 3023 may be, respectively, likethe layers 32, 33 in U.S. Pat. No. 5,417,858. Optional sides 3024 may belike the channel shaped members 23 in U.S. Pat. No. 5,417,858 or may beany known hookstrip or frame sides.

Sewing material 3025 is used to sew and secure the layers 3022, 3023 tothe plate 3021; and sewing material 3026 may be used to sew and securethe layers 3022 and 3023 together. As shown the size (diameter) of thesewing materials 3025, 3026 (and also of the material of the sewinglines in FIGS. 56–58) is, for some embodiments, greatly exaggerated andcould be depicted by a single point in the drawing; but it is within thescope of the present invention to use sewing material—yarn, cord, line,thread, wire, etc.—of any suitable diameter. For any stitch, knot,series or line of stitches and/or series or line of knots disclosedherein for any screen assembly or screen according to the presentinvention, a staple or a series of staples may be used. Such staple(s)are applied with any suitable known stapling machine or apparatus and/orby hand. Either individual separate stitches or knots of sewing materialmay be used for the screen assembly 3020 (and for any screen assemblydisclosed herein); or lines of sewing material in any desired stitch orstitch pattern (e.g. as the lines of the screen assembly 3000) may beused.

FIG. 61 shows an alternative configuration for the layers of screeningmaterial in which ridges and valleys have a more rounded shape (viewedin cross-section) as compared to the screening material of FIG. 60.Also, optionally, a third layer of screening material 3027 is beneathtwo upper layers of screening material 3028, 3029. A plate 3021 a islike the plate 3021, FIG. 59. Sewing material 3025 a is like screeningmaterial 3025, FIG. 59 and sewing material 3026 a is like screeningmaterial 3026, FIG. 59. The layers 3027–3029 may be as the layers 77,79, 80 in U.S. Pat. No. 5,417,858; or they may be made of any desiredscreening material and/or mesh, metal or synthetic, as may be any layerdisclosed herein. In addition to securement together with sewn sewingmaterial, any part or substantially all of the surface area of thelayers around openings in the plate 3021 may be bonded or adhered withsuitable material, glue or adhesive. In one aspect, screening layers arethus bonded together and the combination of these layers is sewn to theplate, or vice-versa (as can be done with any screen assembly disclosedherein).

FIG. 62 illustrates a version of the screen assembly of FIG. 61 in whichone or more individual stitches 3030–3032 extends through and from thescreening layers 3027–3029 to and through holes or perforations theplate 3021 beneath and within ridges formed by the undulating shape ofthe screening material. Any desired number of such individual stitchesor knots may be used within a ridge, e.g. one, two, three, four, five,or more; or a series of them may be beneath a ridge extending from oneend thereof to the other. Also, the sewing material may extend throughall the layers of screening material or through only one or two layers.If the sewing material is metal and the plate is also, the sewingmaterial may be sintered to the plate; similarly, with metal screeningmaterial and metal sewing material the sewing material may be sinteredto the screening material.

FIG. 62 also illustrates that an area of excessive wear or abrasion in ascreen assembly (any according to the present invention) may have aplurality of either individual stitches or knots of sewing material or aline of a plurality of sewn stitches. As shown in the left-most valley3034 of FIG. G, three stitches of sewing material 3025 are located inthe valley. As shown in the right-most valley 3035 five stitches ofsewing material 3026 secure the screening layers together at thislocation. Also, the tops of ridges of an undulating or corrugated screenassembly may have such a plurality of stitches or knots, an individualstitch or knot, or an individual staple or staples. It is within thescope of this invention to use any desired number of stitches and/orlines of stitches in any area of a screen assembly and, in one aspect,to do so for areas of anticipated excessive wear and abrasion.

FIG. 63 illustrates that according to the present invention a screenidentifier—“No. GLM III”—and/or a logo or trademark—“BIG MC”—can be sewninto a screen 3037. The screen 3037 can be single or multi-layer (andcan be any screen assembly disclosed herein).

FIG. 64 illustrates a screen 3040 according to the present inventionwhich has different stitching patterns 3041, 3042, 3043 with differentstitch densities in different areas of a screen. The screen 3040 may beany screen or screen assembly disclosed herein and the sewing materialfor the stitches may be any sewing material disclosed herein. Any one ortwo of the patterns 3041–3043 may be deleted. It is also within thescope of this invention to use any desired pattern of stitching at anylocation on a screen.

It is also within the scope of this invention to delete the plates(3001, 3021) from the embodiments of FIGS. 56 and 59 and to use aplurality of stitches, knots, and/or lines thereof (all in one generaldirection parallel to each other or a plurality of intersecting lines)instead of such a plate; and such a plurality of stitches, etc., is nota legal equivalent of any frame or of any plate as in U.S. Pat. Nos.4,575,421; 5,783,077; 5,720,881; 5,417,793; 5,417,859; or U.S. Pat. No.5,417,858. It is also within the scope of this invention to delete theplate or frame from any of the subject matter of U.S. Pat. Nos.4,575,421; 5,783,077; 5,720,881; 5,417,793; 5,417,859; and 5,417,858 (orfrom any known flat or 3-D screen assembly) and to use instead aplurality of stitches, knots, and/or lines of sewn sewing material. FIG.65 shows a version of a screen as in FIG. 61 but with no plate 3021.Pluralities of lines (as viewed from above) of stitching material 3025 aand 3026 a extend across the screen assembly from one side to the other.Other lines (not shown) may be provided at an angle or perpendicular tothese lines of material 3025 a and 3026 a.

FIG. 66 shows a flat screen 3041 with layers as in U.S. Pat. No.4,575,421 (or any multi-layer screen disclosed or referred to herein),but with no lower plate. Lines of stitching 3042 extend across thescreen 3041 from one side to the other. Other lines (not shown) may beprovided at an angle or perpendicular to the lines 3042. As shown inFIG. 61, a stitch or line of sewing material 3045 may be used to preventa ridge of screening material from expanding and/or flattening. Anydesired number of such lines or stitches may be used along the length ofa ridge (including any ridge or ridges of a series of ridges on anyscreen including any screen disclosed herein).

FIG. 67 illustrates steps in a method according to the present inventionfor producing screen assemblies according to the present invention. Apiece of screening material 3052 of relatively fine mesh (e.g., but notlimited to, 24 mesh to 500 mesh; made, e.g., of metal, steel, stainlesssteel, natural fiber such as cotton, or synthetic material such asnylon, polyester, polypropylene, polyethylene, or KEVLAR™ material) iscombined with a piece of screening material 3054 of a medium mesh (e.g.,but not limited to, 32 mesh to 400 mesh made, e.g. of the materials asfor piece 3052) and a piece of screening material 3056 of coarse mesh(e.g., but not limited to, 1 mesh to 30 mesh made, e.g., of thematerials as for piece 3052). It is within the scope of this inventionto add an additional layer of screening material as any of the pieces3052, 3054, 3056 and to position it on top of any of the other piecespresent. It is within the scope of this invention to delete any of thepieces 3052, 3054, or 3056. The straight sides of the glue pattern 3058may be deleted.

Optionally a glue pattern, e.g. as in the glue pattern 3058 is appliedto the screening material piece 3052. Alternatively, or additionally,such a glue pattern is applied to piece 3054 and/or piece 3056. Glue (orany suitable plastic, flexible adhesive, or fusible material) in anypattern or configuration may be used for the glue pattern. In certainaspects a glue pattern is applied over substantially the entire area ofpiece(s) of screening material, in one aspect to coincide with astitching pattern, so that it a. inhibits during handling or use tearingof screening material between stitches and/or holes made by a sewingneedle; b. seals around sewing material, etc.; and/or c. so that glue“heals” holes made by a sewing needle passing through the glue when theneedle is retracted—i.e., the glue around a hole tends to contractsomewhat back into the hole reducing the hole size or substantiallyclosing off the hole. Glues and materials that may be used include anyknown in the art, any disclosed above, and, PUR glues, polyethylene,rubber, nylon, plastic, polyurethane, silicone, any suitable adhesiveand epoxy. Optionally a piece of solid plastic corresponding to thestitching pattern, with or without perforations over its surface area,is used instead of or in addition to a glue pattern. Any glue, epoxy, orother adhesive may be used solely to prevent tearing; or it may also, incertain aspects, be applied in such a manner that it also bondsscreening layers together and/or to a lower plate, frame, or support. Asolid plastic piece may be molded with perforations or the perforationsmay be made after the piece is made.

Optionally strips 3063 of screening material may be applied along edgesof the piece 3052 (and/or along edges of any of the other pieces 3054,3056) for a purpose described in detail below. The strips 3063 are alsoshown on the piece 3052.

The combined structure 3050 (including pieces 3052, 3054, 3056) is gluedor bonded together or sewn together in any manner as described hereinusing any stitch or sewing pattern as described herein. In one aspect,the stitching follows the glue pattern 3058 with the needle or needlespiercing the glue. Such a structure, without further processing, issubstantially flat and may be used in a substantially flat screenassembly. It is within the scope of this invention to sew together onlythe pieces 3052, 3054 or 3056 and to glue or bond the other piece tothem.

In one aspect the structure 3050 is, optionally, notched, with notches3059 along its edges, and is also corrugated (see FIG. M). As shown inFIG. N, prior corrugating, one or more splines of epoxy or plastic 3067may be applied to the structure for added strength and rigidity.Alternatively or in addition to the splines, additional lines of sewingstitches may be used. Ends 3064 of ridges 3066 of the corrugatedstructure are either plugged, covered with material (perforated orunperforated, solid or mesh or screening material), or, as shown, ends3068 (see FIG. 68) are formed of the screening material. Alternatively,an additional strip or strips of screening material, mesh, or acombination thereof (as described above) are added (e.g., but notlimited to the strips 3063) and the ridge end coverings are formed ofthese strips. In one aspect the formed ends are the ends and/or bulbousends described in co-owned pending U.S. application Ser. No. 09/634,610filed Aug. 5, 2000 and incorporated fully herein for all purposes. Anyscreen or screen assembly in U.S. Ser. No. 09/634,610 may have layersconnected together by sewing as described herein.

The resulting structure 3060 may, according to the present invention, becombined with a lower support mesh piece 3070 [e.g. made of steel, wire,composite, or other suitable (zinc, brass, bronze, aluminum, or anyalloy thereof or combination thereof) material or metal with meshranging between one mesh and ten mesh, in one aspect four mesh] or witha lower support plate or series of support strips. Flat top wire clothmay be used for the piece 3070.

In one aspect a screen assembly 3080 (like the structure 3060) ismounted with the structure 3060 on a piece 3070, producing a screenassembly 3090 (like screen assemblies disclosed in U.S. application Ser.No. 09/634,610 filed Aug. 5, 2000). The piece 3070 may be connected tothe other parts by sewing as described herein; by welding; withfasteners; and/or with glue or epoxy.

A version 3094 of the screen assembly 3090 has side hookstrips 3091 formounting of the screen assembly to a vibratory separator forliquid/solid and/or solid/solid separation e.g., but not limited to, ashale shaker for treating drilling fluid or mud with drilling solids,debris, and/or cuttings entrained therein. A version 3092 of the screenassembly 3090 includes a frame with sides 3095, 3096, 3097 and 3098.Optionally cross support members 3099 may be included in the frame.

FIG. 73 shows a screen assembly 3100 according to the present inventionwhich is like the screen assembly of FIG. 56 (like numerals indicatelike parts). Instead of the thread and stitching of the screen assemblyof FIG. 56, the screen assembly 3100 has lines of staples (or rivets)3102, 3104 and 3106, 3108.

In certain aspects the thread, etc. used for three-dimensional screensand screen assemblies of the present invention is used in such a patternand location that it presents a projecting series of thread parts thatproject out from ridges of a screen. Viewing such a ridge 3130 from theside as shown in FIG. 74, the thread portions 3132 direct solids flowinggenerally in the direction of the arrow in FIG. 74 up or down the ridge.This increases the length of travel of these solids from one end of thescreen to the other (they do not travel in a straight line across thescreen) and thereby increases their time on the screen surface so thatliquids have more time to leave the solids and pass through the screen.

Any ramp base or portion described above that is connected to a screen,mesh, or layers thereof may be connected by sewing (or staples) above asdescribed above; or in addition to the connection or securement methodpreviously described sewing (or staples) as described above may also beused.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a screen assembly for a vibratory separatorapparatus or shaker, the screen assembly with at least two screeningmembers, and the at least two screen members connected by sewingmaterial. Such a method may include one or some of the following, in anypossible combination: the at least two screening members comprise aplurality of layers of screening material; the plurality of layers ofscreening material include at least a first fine screen layer and asecond coarse screen layer; wherein the sewing material is thread;wherein the sewing material comprises a pattern of spaced-apart stitchesover substantially the entire surface of the at least two screenmembers; wherein one of the at least two screen members is a perforatedplate; wherein the at least two screening members includes at least onethree-dimensional screening member; wherein the at least onethree-dimensional screening member is made of screening material;wherein the screening material is a plurality of layers of screeningmaterial; one of the at least two screening members comprising a base,and the plurality of layers of screening material connected to the base;wherein the base is a perforated plate; wherein the plurality of layersof screening material are connected to the base with sewing material;the sewing material comprises a plurality of spaced-apart staples;wherein the base is a layer of coarse mesh; wherein the at least twoscreening members is at least two layers of screening material and aperforated base, the at least two layers of screening material sewntogether to form a combined screen, the combined screen sewn to theperforated base; the sewing material comprising thread in a stitchpattern across the at least two screening members, a pattern ofexpandable material (e.g. rubber, glue, plastic, etc.) on andcorresponding to the stitch pattern, and the thread passing throughholes in the pattern of expandable material, the expandable materialexpanded within the holes following extraction of a needle therefrom,the needle used to apply the sewing material, to inhibit tearing ofeither of the at least two screening members between holes; multiplestitches of sewing material adjacent each other in areas of increasedwear of the screen assembly; and/or wherein the at least two screeningmembers includes three-dimensional screening material with a pluralityof alternating ridges and troughs, at least one series of stitches ofsewing material ascending up a side of a ridge from a top to a bottomthereof, and the at least one series of stitches having stitch portionsprojecting out from an outer surface of the ridge for contact by solidparticles flowing over the screen assembly to change direction of travelof the solid particles.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a screen assembly for a vibratory separatorapparatus, the screen assembly with at least two screening members, andthe at least two screen members connected by sewing material, whereinthe sewing material comprises thread, the sewing material comprisingthread in a stitch pattern across the at least two screening members, apattern of expandable material on and corresponding to the stitchpattern, the thread passing through holes in the pattern of expandablematerial, the expandable material expanded within the holes followingextraction of a needle therefrom, the needle used to apply the sewingmaterial, to inhibit tearing of either of the at least two screeningmembers between holes, the at least two screening members includingthree-dimensional screening material with a plurality of alternatingridges and troughs, at least one series of stitches of sewing materialascending up a side of a ridge from a top to a bottom thereof, and theat least one series of stitches having stitch portions projecting outfrom an outer surface of the ridge for contact by solid particlesflowing over the screen assembly to change direction of travel of thesolid particles.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a vibratory separator apparatus including avibratory shaker device, a screen assembly mounted on the vibratoryshaker device and with at least two screening members, and the at leasttwo screen members connected by sewing material.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a method for treating material, the methodincluding introducing the material to a vibratory separator apparatus,the vibratory separator apparatus with a vibratory shaker device, ascreen assembly mounted on the vibratory shaker device and with at leasttwo screening members, and the at least two screen members connected bysewing material, and screening the material with the at least twoscreening members to separate components thereof, the at least twoscreening members vibrated by the vibratory shaker device. In one aspectin such a method the material is drilling fluid with solids therein.

FIG. 72 shows a screen assembly 3150 according to the present inventionwhich has a layer of screening material 3152 over a series of supportstrips 3154. Side hook strips 3156 provide for mounting of the screenassembly. Alternatively, a frame or perforated plate may be used(although there are not legal equivalents of a series of support stripsand they are not the legal equivalent of a screen with layers sewntogether and they are not the legal equivalent of a lower supportingcoarse mesh). The screening material 3152 may be: any screening materialor mesh disclosed herein or any combination of layers thereof disclosedherein or any suitable layer or layers of screening material.

A piece 3160 of screening material is sewn (or connected with rivetsand/or staples) to the screening material 3152 with stitching 3161. Asolid piece of material 3162 is sewn to the screening material 3152 withstitching 3163, 3165. A perforated piece of material 3164 with aplurality of perforations 3166 is sewn to the screening material 3152.Any one or two of the pieces 3160, 3162, 3164 may be deleted. Stitches3168 sewing the piece 3164 are surrounded by an amount of glue 3170 thatextends around stitch holes through the piece 3164 and around portionsof stitches through the screening material 3152.

It is within the scope of this invention for any hole for any sewingmaterial, rivet or staple to have such glue as glue 3170 around it orany other material that will contract around the sewing material, etc.upon removal of a needle and will contract around a part of a rivet orstaple to help “heal” a hole and to seal around the material, etc.

It is within the scope of this invention to have a plurality of pieceslike the piece 3160 (two, three, four, five, six or more) spaced-aparton the screening material 3152. Similarly there may be multiple pieces3162 and/or 3164 in any position or desired combination with or withoutpieces 3160. In certain aspects a piece or pieces 3160, 3162, and/or3164 are wed at locations of relatively high or excessive screen wear.Any such piece or pieces may be used on any two-dimensional orthree-dimensional screen, either on top of or beneath (or both)screening material.

FIGS. 75A and 75B show a screen assembly 3200 according to the presentinvention which has a layer 3202 of coarse mesh and side hooks strips3205. On the coarse mesh layer 3202 are sewn two offset series ofridges/valleys 3204, 3206.

Sewing material 3210 is sewn in a desired pattern across substantiallyall of the surface area (as viewed from above as in FIG. 75A) of thescreen assembly.

A middle portion or strip 3212 of the screen assembly 3200 includes alayer 3214 of fine mesh (e.g. but not limited to 200 mesh) on a layer ofless-fine mesh (e.g. but not limited to 19 mesh, not shown). These twolayers extend for a length 3216. A similar strip (like the strip 3212)is used at each end 3218, 3219 of the screen assembly 3200 between theridge/valley parts and the coarse layer 3202.

The sewing material 3210 may be used only in selected areas of thescreen assembly instead of over substantially all of its area. Glue orother material may be used in the same pattern as the stitching to closeoff and/or “heal” or seal holes or the area around the outer surface ofstitching material (or rivets or staples). In one aspect the sewingmaterial is KEVLAR™ thread between 0.063 and 0.045 inches in diameter.Thread of circular, oval, or elliptical cross-section may be used. Forany screen or screen assembly herein, the sewing material may be anythread, including but not limited to moisture-resistant ormoisture-absorbing thread or may be any wire of circular, oval, orelliptical cross-section. In another aspect, ends of peaks and valleys,instead of being located at the end boundaries of the screen assembly asshown in FIG. 75A, are spaced-apart from their ends. In one particularaspect of such a screen assembly, the peaks and valleys ends are formedintegrally of screening material that is pushed out from an initialrelatively flat layer or layers so that there are never any open endsthat need to be closed off or sealed (as for the example the open endsof the screen assemblies of U.S. Pat. Nos. 5,417,793; 5,417,858;5,417,859).

In one particular embodiment of the screen 3200 the ridge/valleyportions 3204, 3206 are made from multi-layer pieces of screeningmaterial sewn together with ridges with integral bulbous ends pushed outfrom the screening material. The ridge/valley portions 3204, 3206 arethen placed on the strips 3212 and the end strips (like the strip 3212)and sewn thereto. The resulting structure is then sewn to the layer3202. alternatively the structure may be produced by gluing or usingepoxy to bond layers together (which is not the legal equivalent ofmechanically connecting the layers together with sewing material,rivets, or staples). Alternatively the structure (sewn or bonded) may beconnected to the coarse layer by gluing or using epoxy—or both methodsmay be used on a single screen assembly.

In any screen according to the present invention when sewing material(rivets, or staples) is used instead of glue, epoxy, or plastic and thesurface area of the thread presented to material to be treated is lessthan that of the glue, epoxy, or plastic, then there is that much moreincreased open area of screening material for screening the material tobe treated. Also with such a screen according to the present inventionthere is more relative movement between layers which tends to reduce orprevent screen blinding and plugging. Certain pipe dopes stick toplastic on a screen and inhibit the conveyance of solids—which isreduced by using non-plastic sewing material in certain screensaccording to the present invention. According to the present inventionscreens with different thread or other sewing material can be quicklychanged in response to changes in conditions such as temperaturechanges, fluid changes, or chemical changes. Alternatively, or inaddition to sewing the pieces of the strips 3212 and the end stripstogether, the pieces may be bonded together with epoxy 3213. Similarlyepoxy may be used to bond the layer 3202 to the other parts. The ends ofthe ridge/valley portions 3204, 3206 (when there are initially openends) may be closed off in any known manner with plugs, screeningmaterial, etc. In certain aspects this may be done with screeningmaterial of a mesh size like that of the ridge/valley portions. Sewingmaterial, rivets, and staples are not the legal equivalent of eachother. Any ramp disclosed herein may be attached to a lower support orlower layer by any sewing method disclosed herein (or by rivets and/orstaples). Any end of any screen disclosed herein that is initially openmay be closed off and/or sealed by connecting material over the open endby any sewing method and/or rivets, and/or staples disclosed herein.

FIG. 76A shows a screen assembly 3300 according to the present inventionfor a vibratory shaker or shale shaker which has a first part 3302 and asecond part 3304. The second part 3304 is connected to or formedintegrally of the first part 3302. In one particular aspect an originalgenerally flat screen is folded along a line 3303 to form the secondpart 3304. In other embodiments a separate piece forms the second part3304 and it is positioned adjacent and/or connected [e.g., but notlimited to: by sewing; by welding; tack welding; glue; adhesives;soldering; sintering; connectors (e.g. but not limited to bolts,staples, screws, releasably co-operating fastener material such asVelcro (™) material, rivets); and/or sintering] to the first part 3302.When separate pieces are used, in one aspect, the basket has separatemounting structure and/or devices for each piece (e.g. but not limitedto hookstrip structures; spring tension bolts; wedging structures and/orapparatus, brackets and/or channel structures in which screen parts orframes are positioned; releasable locking devices; clamps, etc.). Inother aspects a frame (see e.g. FIG. 79) has frame support portionscorresponding to the parts 3302 and 3304 and each part is connected toits corresponding frame portion. In one aspect the part 3304 is aseparate piece held or mounted in a basket (e.g. as basket 3310, FIG.76B or in any known suitable basket); held or mounted with any knownsuitable mounting structure or device (as may be any screen or screenpart disclosed herein). The part 3302 is then installed so that it holdsthe part 3304 in place, with a portion of the part 3302 contacting andabutting a top portion of the part 3304. In one aspect such contact is asealing contact. Optionally a gasket or other suitable sealing materialmay be used between the parts 3302 and 3304 where they abut each other(as may be the case with any two screens or screen parts herein).

As shown the angle 3305 between the first part 3302 and the second part3304 is about ninety degrees. It is within the scope of this inventionfor the angle 3305 to be any desired angle and, in certain aspects, thisangle ranges between forty-five and ninety degrees and in other aspectsto range between forty-five and one hundred thirty five degrees.

The second part 3302 has screen mesh 3306 for the first part 3302 andscreen mesh 3308 for the second part 3304. These screen meshes may beidentical, e.g. but not limited to, both fine screen material or bothcoarse screening material; or they may be made of different screeningmaterial. It is also within the scope of this invention for either orboth parts 3302, 3304 (as with any screen or screen part herein) toinclude multiple (two, three, four or more) flat or 3-dimensional (e.g.corrugated; undulating) layers of screening material and/or mesh,including, but not limited to, any combination of layers disclosed orreferred to herein; bonded, connected, sintered and/or sewn together (ornot) as any disclosed or referred to herein; and with any shape screenopenings including, but not limited to square, diamond-shaped, hexagonaland rectangular—and any such layer(s) may be bonded to a support and/orsupport layer(s) [e.g. but not limited to a support layer of coarsemesh; a perforated plate; a strip support; or a frame]. Either part3302, 3304 that has multiple layers of screening material may have thelayers free of each other (i.e., unbonded, unconnected, etc.) and thelayers [all layers and/or support layer(s)] may be flattened and/orcalendered together or not. In one particular aspect a unitary supportstructure is formed in a shape corresponding to the final positioning ofa two part screen (e.g. as with parts 3302, 3304 as shown in FIG. 76A)and one or more screen layers are then applied and/or connected and/orbonded to the unitary support. Alternatively a two part support is madeand the two parts are connected—one for a first screen part (e.g. part3302) and one for a second screen part (e.g. part 3304).

FIG. 76B shows a typical basket 3310 for a vibratory separator apparatuswith two screen assemblies 3300 placed end-to-end therein. Any suitableknown mounting apparatus and/or devices may be used to mount (in certainaspects, releasably mount) the screen assemblies 3300 in the basket3310. The basket 3310 has a first end 3311 at which material to behandled by a vibratory separator is introduced into the basket; sides3312 and 3314; and a material exit end 3313. Material passing throughthe screen assemblies 3300 falls through them and then through an openbottom 3316 of the basket 3310 or onto another screen assembly below theassemblies 3300. An optional splash plate (not shown) over part of thescreen at a fluid introduction end may be used in the basket 3310 ontowhich material is fed before it flows over the screen assembly 3300 atthe first end 3311.

As shown there are two screens 3300 in the basket 3310; but the screens3300 may be any suitable length so that any desired number of screenassemblies (e.g. three, four, five or more) may be disposed end-to-endin the basket 3310. It is also within the scope of this invention todelete a screen assembly 3300 (or screen assemblies 3300 when there arethree or more) from the basket 3310 and replace it (or them) with anysuitable known screen assembly, including, but not limited to any screenassembly disclosed or referred to herein—e.g. known screen assembliesand/or screen assemblies according to the present invention.

It is within the scope of the present invention to use two or morescreen assemblies 3300 stacked one on top of the other in the basket3310. It is within the scope of this invention to use one or more screenassemblies 3300 (and/or any screen assembly disclosed in FIGS. 77A–88)with any basket as disclosed in U.S. application Ser. No. 09/716,176filed Nov. 17, 2000 incorporated fully herein for all purposes andco-owned with the present invention.

FIGS. 76C–76E show screens S₁–S₆ similar to those of FIGS. 76A and 76B;but the screen S₁ has a lower lip 3301 upon which an end of the screenS₂ sealingly rests, is positioned, or is connected (e.g., but notlimited to, by glue; adhesive; connectors such as screws, staples, nutsand bolts; welding; tack welding; releasably cooperating fastenermaterial—e.g. Velcro (™) material; clamps; and/or rivets). The screen S₃has a lower lip 3303 under which rests an end of the screen S₄. This endof the screen S₄ is in sealing contact with the lip. Each screen S₁, S₃,and S₅ has an optional splash plate or impact plate 3307 which fluidintroduced onto the screen hits initially then flows onto the screen.Instead of the lips 3301, 3303, a tongue-in-groove structure 3309 isused on the screws S₅, S₆ (FIG. 76E) to sealingly connect one screen toanother—with an end of the screen S₆ positioned in a groove of thescreen S₅. Sealing material and/or a gasket may be used in the grooveand/or on the end of the screen S₆ in the groove. Any seal structurementioned above may be used with any screens disclosed in FIGS. 76A–88(and with any screen disclosed herein).

FIG. 77A shows a screen assembly 3320 according to the present inventionwhich has two side portions 3322, 3324 of screening material and betweenthem a raised portion 3326 that includes sides 3327, 3328 that meet atan apex 3325. The screening material may be any as described for thescreen assembly 3300 in any combination of layers or form as describedfor the screen assembly 3300. As shown the apex 3325 is about fourinches above the screen portions 3322, 3324 and the angle between thesides 3327, 3328 is about sixty degrees. This angle can be any suitabledesired angle and, in certain aspects, ranges between thirty and ninetydegrees. The apex 3325 may be any desired height above the screenportions 3322, 3324 and, in certain embodiments, is between one and sixinches above the screen 3322, 3324 and in one aspect is at least one—anda half or at least two inches above the rest of the screen. It is withinthe scope of this invention to have one, two, three, four or more raisedportions 3326 spaced-apart on a screen assembly such as the screenassembly 3320; and the cross-section of such raised portions viewed onend may be as shown in FIG. 77A or of an end shape as shown for anyraised portion, insert or ramp disclosed herein. The bottom of theraised portion 3326 may be open; may have a plurality of spaced-apartstrips or bars across it; may be plugged; may have mesh or screencovering it; or may have a solid sheet or piece blocking it off.Similarly, the open ends of the raised portion 3326 may be open or haveany of the structures possible as listed for the bottom of the raisedportion 3326. In one aspect the raised portion is made of an integralmount of a screen so that there are no open ends of the raised portion.In one such screen an amount of screening material is pushed out fromthe screen to form the raised portion(s).

FIG. 77B shows a basket 3329 (like the basket 3310) with a screenassembly 3320 mounted therein. Shown schematically is a second screenassembly 3321 (shown schematically with a blank surface) which may belike the screen assembly 3320, the screen assembly 3300, or any otherscreen assembly disclosed or referred to herein. One, two, or morescreen assemblies 3320 may be stacked one on top of the other; and onescreen assembly 3320 may be inverted on top of another so that the apexof the raised portion(s) of the inverted screen assembly points downinstead of up (and if so inverted the layers of screen material may alsobe rearranged with finer material on top).

FIG. 78 shows a screen assembly 3330, like the screen assembly 3300,with side hookstrips 3331, 3332 for mounting the screen assembly in abasket. (Such hookstrips may be provided for any screen or screen partdisclosed herein.) Hookstrips may also be provided for the downwardlyprojecting part of the screen.

FIG. 79 shows a screen assembly 3334, like the screen assembly 3300,with the screening material mounted on a frame with frame parts 3335 and3336. Any known frame structure may be used for the parts 3335 and 3336.Alternatively a perforated plate or sheet metal with holes, openings,apertures or perforations may be used (for any screen assembly 3310,3320, 3340, 3344) under either or both screen portions or a stripsupport with a series of support strips (which is not the legalequivalent of a perforated plate or of a frame with a grid ofcrossmembers) may be used.

FIG. 80 shows a screen assembly 3340, like the screen assembly 3320,with side hookstrips 3341, 3342 for mounting the screen assembly in abasket. Any suitable lower support may be used with this screen.

FIG. 81 shows a screen assembly 3344, like the screen assembly 3320,with the screen portions mounted on a frame 3345. Any known framestructure may be used.

FIG. 82 shows a screen assembly 3350 according to the present inventionwith a top portion 3352 like the screen assembly 3320, FIG. 77A [or likeany screen assembly discussed herein with a raised portion or portionswith an apex (or apices)]; and with a portion 3354, like the portion3304 of the screen assembly 3300, FIG. 76A (or like such a portion ofany screen assembly disclosed above).

Any of the screen assemblies of FIGS. 76A–88 may be used, e.g., in theapparatuses of FIGS. 33 and 34B discussed above. Any screen assembly inFIGS. 76A–88 may employ any known support as a lowermost structure,including, but not limited to, known perforated plates; aperturedplates; sheet metal with holes, perforations, openings, or apertures;strip supports; frames; very coarse mesh; and/or expanded metal.

FIGS. 83–85 show various ways according to the present invention forproviding a connection across the end of a raised portion 3326 of ascreen assembly according to the present invention. In FIG. 83 two crossstrips 3326 a and 3326 b are connected to sides of the raised portion3326 to provide strength and to prevent the sides of the raised portionfrom separating apart. This is done in FIG. 84 with a piece of screen3326 c and in FIG. 85 with a solid plug 3326 d. Any known connector,securement, securing means, or connection means may be used to connectthe items 3326 a–3326 d over the ends of the raised portion 3326. In oneaspect only one of the cross strips is used. It is to be understood thatboth ends of the raised portion (of any screen disclosed herein) mayhave any or any combination of the items 3326 a–3326 d. Also any ofthese items may be used with any of the structures in FIGS. 86–88.

FIGS. 86–88 show structures on the bottom of a screen SCN that has araised portion 3326 which prevent the sides of the raised portion fromseparating. FIG. 86 shows a solid strip, sheet, or plate 3326 e (whichmay also be perforated and/or have holes, openings, and/or aperturesthrough it). FIG. 87 shows a plurality of strips or bars 3326 f and 3326g connected between sides of a raised portion 3326. Any one, two orthree of the strips or bars may be omitted; and any such additionalstrips or bars may be added. FIG. 88 shows a piece of screen mesh 3326 hconnected between the sides of a raised portion 3326. Any suitablescreen, expanded metal, or mesh may be used. The items 3326 e–3326 h maybe connected across the raised portion to its sides by any connection orattachment means or method disclosed herein.

FIGS. 89A and 89B illustrate that any screen or screen portion of FIGS.76A–88 may have a three-dimensional layer or layers of screen material3361 on a support 3364 (any known support), optionally with mountingstructure 3362 (which may be any known suitable mounting apparatus,mounting device, draw-bar-bolt structure, hookstrips, etc.). Thematerial 3361 may be any known multi-layer screening material, screen,and/or mesh, including, but not limited to, those disclosed herein.

FIG. 90 shows (partially) a screen according to the present inventionwith a raised portion 3326 (as in FIG. 85). A pool, mass, or cake ofmaterial to be screened 3365 has an upper surface 3366 at a height habove a base of the raised portion 3326. Preferably the raised portion'stop 3326 t (and the top of any raised portion disclosed herein, FIGS.77–88) is at least one inch, more preferably at least one and a halfinch, and most preferably at least two inches above the surface 3366.Typically the tops of the ridges of prior art three-dimensional screensare not more than an inch above a pool or mass of material to bescreened.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a screen assembly for a vibratoryseparator, the screen assembly with a first screen portion having afirst end and a second end spaced apart from the first end, a secondscreen portion adjacent the second end of the first screen portion, thesecond screen portion projecting down from the second end of the firstscreen portion. Such a method may also include one, some (in anypossible combination) or all of the following: the second screen portionhaving a seal structure for sealingly abutting an end of another screenassembly; wherein the seal structure is a lip projecting from the secondend of the screen; wherein the seal structure includes a groove on thesecond screen portion for receiving an end of another screen; whereinthe first screen has a width and the second screen has a width that, inone aspect, is between 1% to 30% of the width of the first screen;wherein the first screen portion is substantially flat or isthree-dimensional; wherein the second screen portion is substantiallyflat or is three-dimensional; wherein the first screen portion includesa plurality of at least two layers of screening material; wherein thesecond screen portion includes a plurality of at least two layers ofscreening material; a support beneath the screen assembly layers; afirst support beneath and supporting the first screen portion; a secondsupport beneath and supporting the second screen portion; wherein thesecond screen portion is at an angle to the first screen portion theangle between forty five and one hundred thirty five degrees; at leastone raised portion projecting upwardly from the first screen portion;the at least one raised portion having two open ends or formed of ascreen layer without initially having open ends; wherein the open endseach have a plug therein; wherein the at least one raised portion hastwo spaced-apart sides and the screen has at least one connection member(e.g. but not limited to a strip or strips) connecting the sides of theat least one raised portion together; wherein the at least oneconnection member is at least one strip across each of the open ends ofthe at least one raised portion; wherein the at least one connectionmember is between the open ends of the at least one raised portion andat a bottom of the spaced-apart sides thereof; wherein the at least oneraised portion has spaced-apart sides with at least one connectionmember connected to and between the spaced-apart sides to prevent themfrom separating; wherein the at least one raised portion has a top partat least one-and-a-half inches or at least four inches above the firstscreen portion; side hookstrips on the first screen portion and/or onthe second screen portion for mounting the screen assembly in a basket;wherein the second screen portion is formed integrally with the firstscreen portion; wherein the first screen portion is a first screen andthe second screen portion is a second screen contacting the firstscreen; wherein the at least one raised portion extends from a first endof the first screen portion at which fluid to be treated by the screenassembly is introduced onto the first screen portion to a second end ofthe first screen portion, the at least one raised portion extendingacross a width of the first screen portion; wherein the at least oneraised portion has two sides meeting at a top of the raised portion atan angle; wherein the angle ranges between 30 and 60 degrees; and/or theraised portion having a shape in an end view that is semi-circular, halfoval, three sides of a square or rectangle, or with two straight sidesand a curved top.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a screen assembly for a vibratoryseparator, the screen assembly with a first screen portion having afirst end and a second end spaced apart from the first end, a secondscreen portion adjacent the second end of the first screen portion, thesecond screen portion projecting down from the second end of the firstscreen portion, and at least one raised portion projecting upwardly fromthe first screen portion.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a method to separate components of amaterial with a vibratory separator apparatus, the vibratory separatorapparatus with a frame, at least one screen assembly positioned withinthe frame for introduction thereon of the material to separatecomponents thereof, at least one vibrator connected to the frame forvibrating the frame and the at least one screen assembly, the methodincluding introducing the material onto the screen assembly, the screenassembly with a first screen portion having a first end and a second endspaced apart from the first end, a second screen portion adjacent thesecond end of the first screen portion, the second screen portionprojecting down from the second end of the first screen portion, andseparating components of the material with the first screen portion andthe second screen portion.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a method to separate components of amaterial with a vibratory separator apparatus, the vibratory separatorapparatus with a frame, at least one screen assembly positioned withinthe frame for introduction thereon of the material to separatecomponents thereof, at least one vibrator connected to the frame forvibrating the frame and the at least one screen assembly, the methodcomprising introducing the material onto the screen assembly, the screenassembly comprising a first screen portion having a first end and asecond end spaced apart from the first end, a second screen portionadjacent the second end of the first screen portion, the second screenportion projecting down from the second end of the first screen portion,at least one raised portion projecting upwardly from the first screenportion, and separating components of the material with the first screenportion and the second screen portion.

The present invention, therefore, provides in certain, but notnecessarily all embodiments, a screen disclosed herein with at least oneraised portion projecting upwardly from the first screen portion, theraised portion having a top, wherein the material with components to beseparated flows over a top surface of the first screen portion, saidmaterial having a top surface, the top of the raised portion above thetop surface of the material; wherein the top of the raised portion is atleast one inch above the top surface of the material; or wherein the topof the raised portion is at least two inches above the top surface ofthe material.

In conclusion, therefore, it is seen that the present invention and theembodiments disclosed herein and those covered by the appended claimsare well adapted to carry out the objectives and obtain the ends setforth. Certain changes can be made in the subject matter withoutdeparting from the spirit and the scope of this invention. It isrealized that changes are possible within the scope of this inventionand it is further intended that each element or step recited in any ofthe following claims is to be understood as referring to all equivalentelements or steps. The following claims are intended to cover theinvention as broadly as legally possible in whatever form it may beutilized. The invention claimed herein is new and novel in accordancewith 35 U.S.C. § 102 and satisfies the conditions for patentability in §102. The invention claimed herein is not obvious in accordance with 35U.S.C. § 103 and satisfies the conditions for patentability in § 103.This specification and the claims that follow are in accordance with allof the requirements of 35 U.S.C. § 112. The inventors may rely on theDoctrine of Equivalents to determine and assess the scope of theirinvention and of the claims that follow as they may pertain to apparatusnot materially departing from, but outside of, the literal scope of theinvention as set forth in the following claims.

1. A screen assembly for a vibratory separator, the screen assemblycomprising a first screen portion having a top surface and a first endand a second end spaced apart from the first end, a second screenportion connected to the second end of the first screen portion, thesecond screen portion projecting down at an angle from the second end ofthe first screen portion, the first screen portion having firstscreening material thereon with a plurality of spaced-apart holesthrough which fluid is passable, the second screen portion having secondscreening material thereon with a plurality of spaced-apart holesthrough which fluid is passable, the second screening material at anangle to the first screen portion, the second screening material at anangle to the first screening material, the first screen portion adjacentthe second screen portion so that a flow including fluid flowing fromthe top surface of the first screening material flows down onto thesecond screening material for separation of fluid by the secondscreening material from said flow including fluid, at least one raisedportion projecting upwardly from the first screen portion, and whereinthe at least one raised portion has a top part at least four inchesabove the first screen portion.
 2. The screen assembly of claim 1further comprising the second screen portion having a seal structure forsealingly abutting an end of another screen assembly.
 3. The screenassembly of claim 1 wherein the first screen portion is substantiallyflat and the second screen portion is substantially flat.
 4. The screenassembly of claim 1 wherein the first screen portion comprises aplurality of at least two layers of screening material, and wherein thesecond screen portion comprises a plurality of at least two layers ofscreening material.
 5. The screen assembly of claim 1 further comprisinga first support beneath and supporting the first screen portion, and asecond support beneath and supporting the second screen portion.
 6. Thescreen assembly of claim 1 further comprising the at least one raisedportion having two open ends.
 7. The screen assembly of claim 6 whereinthe open ends each have a plug therein.
 8. The screen assembly of claim6 wherein the at least one raised portion comprises two spaced-apartsides and the screen further comprising at least one connection memberconnecting the sides of the at least one raised portion together.
 9. Thescreen assembly of claim 8 wherein the at least one connection member isat least one strip across each of the open ends of the at least oneraised portion.
 10. The screen assembly of claim 1 further comprisingside hookstrips on the first screen portion for mounting the screenassembly in a basket.
 11. The screen assembly of claim 1 wherein the atleast one raised portion extends from a first end of the first screenportion at which a flow including fluid to be treated by the screenassembly is introduced onto the first screen portion to a second end ofthe first screen portion, the at least one raised portion extendingacross a width of the first screen portion.
 12. The screen assembly ofclaim 1 wherein the at least one raised portion comprises two sidesmeeting at a top of the raised portion at an angle.
 13. The screenassembly of claim 12 wherein the angle ranges between 30 and 60 degrees.14. A method to separate components of a flow including fluid with avibratory separator apparatus, the vibratory separator apparatuscomprising a frame, at least one screen assembly positioned within theframe for introduction thereon of said flow including fluid to separatecomponents thereof, at least one vibrator connected to the frame forvibrating the frame and the at least one screen assembly, the methodcomprising introducing the flow including fluid onto the screenassembly, a first screen portion having a top surface and a first endand a second end spaced apart from the first end, a second screenportion connected to the second end of the first screen portion, thesecond screen portion projecting down at an angle from the second end ofthe first screen portion, the first screen portion having firstscreening material thereon with a plurality of spaced-apart holesthrough which fluid is passable, the second screen portion having secondscreening material thereon with a plurality of spaced-apart holesthrough which fluid is passable, the second screening material at anangle to the first screen portion, the second screening material at anangle to the first screening material, the first screen portion adjacentthe second screen portion so that a flow including fluid flowing fromthe top surface of the first screening material flows down onto thesecond screening material for separation of fluid by the secondscreening material from said flow including fluid, at least one raisedportion projecting upwardly from the first screen portion, and whereinthe at least one raised portion has a top part at least four inchesabove the first screen portion, and separating components of said flowincluding fluid with the first screen portion.
 15. The method of claim14 further comprising separating components of said flow including fluidwith the second screen portion.
 16. The method of claim 14 wherein thefirst screen portion comprises a plurality of at least two layers ofscreening material.
 17. The method of claim 14 wherein the second screenportion comprises a plurality of at least two layers of screeningmaterial.
 18. The method of claim 14 wherein the screen assembly furthercomprises a first support beneath and supporting the first screenportion.
 19. The method of claim 14 wherein the screen assembly furthercomprises a second support beneath and supporting the second screenportion.
 20. The method of claim 14 wherein the angle between the secondscreen portion is at an angle and the first screen portion is betweenforty five and one hundred thirty five degrees.